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Relationship Between Cycling Mechanics and Core Stability
Abstract
Core stability has received considerable attention with regards to functional training in sports. Core stability provides the foundation from which power is generated in cycling. No research has described the relationship between core stability and cycling mechanics of the lower extremity. The purpose of this study was to determine the relationship between cycling mechanics and core stability. Hip, knee, and ankle joint kinematic and pedal force data were collected on 15 competitive cyclists while cycling untethered on a high-speed treadmill. The exhaustive cycling protocol consisted of cycling at 25.8 km x h(-1) while the grade was increased 1% every 3 minutes. A core fatigue workout was performed before the second treadmill test. Total frontal plane knee motion (test 1: 15.1 +/- 6.0 degrees ; test 2: 23.3 +/- 12.5 degrees), sagittal plane knee motion (test 1: 69.9 +/- 4.9 degrees ; test 2: 79.3 +/- 10.1 degrees), and sagittal plane ankle motion (test 1: 29.0 +/- 8.5 degrees ; test 2: 43.0 +/- 22.9 degrees) increased after the core fatigue protocol. No significant differences were demonstrated for pedaling forces. Core fatigue resulted in altered cycling mechanics that might increase the risk of injury because the knee joint is potentially exposed to greater stress. Improved core stability and endurance could promote greater alignment of the lower extremity when riding for extended durations as the core is more resistant to fatigue.
... The musculature positioning of the core enables the maintenance of a neutral position of the spine and pelvis, functioning in such a way as to protect against injuries to these parts of the body (Stanton, Reaburn, & Humphries, 2004). However, some researchers have found different relationships between core stability (Abt et al., 2007;Nesser, Huxel, Tincher, & Okada, 2008;Nesser & Lee, 2009) and programs related to the development of core stability (Stanton et al., 2004;Tse, McManus, & Masters, 2005;Myer et al., 2006;Thompson, Cobb, & Blackwell, 2007). The core muscles are thought to play a significant role in the transfer of kinetic energy across the trunk to the extremities (Abt et al., 2007;Tse et al., 2005). ...
... However, some researchers have found different relationships between core stability (Abt et al., 2007;Nesser, Huxel, Tincher, & Okada, 2008;Nesser & Lee, 2009) and programs related to the development of core stability (Stanton et al., 2004;Tse, McManus, & Masters, 2005;Myer et al., 2006;Thompson, Cobb, & Blackwell, 2007). The core muscles are thought to play a significant role in the transfer of kinetic energy across the trunk to the extremities (Abt et al., 2007;Tse et al., 2005). Sports performance can be significantly reduced if the extremity muscles are allowed to be much stronger than the core muscles (Tse et al, 2005;Nesser et al., 2008;Nesser & Lee, 2009). ...
... Some research has examined the link between core stability in different sports. The aim was to assess the role of the core in sports performance (Abt et al., 2007;Nesser et al., 2008;Nesser & Lee, 2009). Some other research has considered the economy/performance ratio (Stanton et al., 2004), the speed of movement of the rod head in golfers (Thompson et al., 2007), swimming (Nikolenko, Brown, Coburn, Spiering, & Tran, 2011), rowing (Tse et al., 2005) and balance (Myer et al., 2006). ...
The goal of this research was to examine the contribution of an innovative program that contains football elements to the activity of preschool children in physical education classes. The research was carried out using a quasi-experimental design with two classes of children of preschool age at Preschool Institution "Cika Jova Zmaj" from Pirot, divided into an experimental (18 subjects) and a control group (16 subjects). The standard physical education program and the experimental football program were implemented over the course of 12 weeks, with a total of 36 hours of physical education or training. The results showed that there are statistically significant differences in the active time of the subjects in class in favor of the experimental group and that this difference was the largest in the seventh week. This research proposes the elements of the football game as one of the traditional forms of physical exercise that shall contribute to the comprehensive motor development of preschool children and additionally activate them in physical education classes.
... During cycling, when the core muscles become fatigued, the optimal lower extremity alignment for power production is not maintained. 9 In addition, after muscular workouts, cool-down programs with core stability exercises tend to enhance postural control. Therefore, incorporating core stability into rehabilitation and training programs is critical for pain and injury prevention, as well as to improve performance. ...
... 20 Furthermore, core stability is associated with torso stability during cycling. 4,9 Reduced core stability lowers torso stability, resulting in greater mediolateral trunk motion. Similar to trunk motion, mediolateral head motion in our poor core stability group was larger than in the good core stability group during the cycling test ( Figure 5A). ...
... To maintain postural stability, the preprogrammed core muscle activity reduces trunk lateral motion. 2,6,9,22,23 Thus, the difference in movement strategy can explain the different results. ...
... While some authors have shown the relationship of core muscle strength with variables of athletic performance (Brown and Abani, 1985;Abt et al., 2007;Sato and Mokha, 2009;Sharrock et al., 2011), others have not (Stanton et al., 2004;Tse et al., 2005). When such correlations were found, most of them were weak or negligible (de Bruin et al., 2021). ...
... The rotation of baseball pitchers can be optimized by conserving the momentum produced by the trunk when moving the throwing shoulder with decreased joint loading (Aguinaldo et al., 2007). Moreover, cycling mechanics may be altered by core fatigue and consequently increase the risk of knee injuries (Abt et al., 2007). As the core is relatively resistant to fatigue, improved core muscle endurance and stability may promote greater alignment of lower limbs during a long ride (Abt et al., 2007). ...
... Moreover, cycling mechanics may be altered by core fatigue and consequently increase the risk of knee injuries (Abt et al., 2007). As the core is relatively resistant to fatigue, improved core muscle endurance and stability may promote greater alignment of lower limbs during a long ride (Abt et al., 2007). Core stability is therefore crucial in injury prevention (Leetun et al., 2004). ...
While force-velocity-power characteristics of resistance exercises, such as bench presses and squats, have been well documented, little attention has been paid to load, force, and power-velocity relationships in exercises engaging core muscles. Given that power produced during lifting tasks or trunk rotations plays an important role in most sport-specific and daily life activities, its measurement should represent an important part of the test battery in both athletes and the general population. The aim of this scoping review was 1) to map the literature related to testing methods assessing core muscle strength and stability in sport and rehabilitation, chiefly studies with particular focus on force-velocity-power characteristics of exercises involving the use of core muscles, 2) and to identify gaps in existing studies and suggest further research in this field. The literature search was conducted on Cochrane Library databases, Scopus, Web of Science, PubMed and MEDLINE, which was completed by SpringerLink, Google Scholar and Elsevier. The inclusion criteria were met in 37 articles. Results revealed that among a variety of studies investigating the core stability and core strength in sport and rehabilitation, only few of them analyzed force–velocity–power characteristics of exercises involving the use of core muscles. Most of them evaluated maximal isometric strength of the core and its endurance. However, there are some studies that assessed muscle power during lifting tasks at different loads performed either with free weights or using the Smith machine. Similarly, power and velocity were assessed during trunk rotations performed with different weights when standing or sitting. Nevertheless, there is still scant research investigating the power-velocity and force-velocity relationship during exercises engaging core muscles in able-bodied and para athletes with different demands on stability and strength of the core. Therefore, more research is needed to address this gap in the literature and aim research at assessing strength and power-related measures within cross-sectional and intervention studies. A better understanding of the power-force-velocity profiles during exercises with high demands on the core musculature has implications for designing sport training and rehabilitation programs for enhancement of athletes’ performance and/or decrease their risk of back pain.
... Analysis of the literature revealed ( Table 2) that out of 13 selected studies, seven (54%) investigated the relationship between core (trunk) stability-related variables and functional movement and/or athletic performance (Abt et al., 2007;Nesser et al., 2008;Nesser and Lee, 2009;Chaudhari et al., 2011;Ozmen, 2016;Anand et al., 2017;de Bruin et al., 2021). Three of them (43%) included only variables of athletic performance (Chaudhari et al., 2011;Anand et al., 2017;de Bruin et al., 2021), another three studies (43%) incorporated variables of functional movement and athletic performance (Nesser et al., 2008;Nesser and Lee, 2009;Ozmen, 2016), and one study (14%) focused on changes in the functional movement resulting from compromised core stability (Abt et al., 2007). ...
... Analysis of the literature revealed ( Table 2) that out of 13 selected studies, seven (54%) investigated the relationship between core (trunk) stability-related variables and functional movement and/or athletic performance (Abt et al., 2007;Nesser et al., 2008;Nesser and Lee, 2009;Chaudhari et al., 2011;Ozmen, 2016;Anand et al., 2017;de Bruin et al., 2021). Three of them (43%) included only variables of athletic performance (Chaudhari et al., 2011;Anand et al., 2017;de Bruin et al., 2021), another three studies (43%) incorporated variables of functional movement and athletic performance (Nesser et al., 2008;Nesser and Lee, 2009;Ozmen, 2016), and one study (14%) focused on changes in the functional movement resulting from compromised core stability (Abt et al., 2007). ...
... Neither EG nor CG increase in TV following the 6-week CT intervention; A significant increase in BEV in the EG but not in the CG Implementing of CT with additional rotational exercises with free weights, resistance bands, or medicine balls leads to additional gains in torso rotational strength and potentially improvement in BEV the effect of neuromuscular training on selected parameters of functional movement (Vitale et al., 2018). Regarding the sport, eleven studies (85%) were conducted in team sports, such as baseball, basketball, cricket, football, handball, soccer, and touch ball (Stanton et al., 2004;Nesser et al., 2008;Nesser and Lee, 2009;Chaudhari et al., 2011;Saeterbakken et al., 2011;Ozmen, 2016;Anand et al., 2017;Sannicandro and Cofano, 2017;Kuhn et al., 2019;Felion and DeBeliso, 2020;de Bruin et al., 2021) and two studies (15%) were carried out in individual sports, such as cycling and skiing (Abt et al., 2007;Vitale et al., 2018). ...
Balance and core stabilization exercises have often been associated with improved athlete performance and/or decreased incidence of injuries. While these exercises seem to be efficient in the prevention of injuries, there is insufficient evidence regarding their role in sport-specific performance and related functional movements. The aim of this scoping review is (1) to map the literature that investigates whether currently available variables of postural and core stability are functionally related to athlete performance in sports with high demands on body balance and spinal posture and (2) to identify gaps in the literature and suggest further research on this topic. The literature search conducted on MEDLINE, Scopus, Web of Science, PubMed, and Cochrane Library databases was completed by Google Scholar, SpringerLink, and Elsevier. Altogether 21 articles met the inclusion criteria. Findings revealed that postural stability plays an important role in performance in archery, biathlon, gymnastics, shooting, and team sports (e.g., basketball, hockey, soccer, tennis). Also core stability and strength represent an integral part of athlete performance in sports based on lifting tasks and trunk rotations. Variables of these abilities are associated with performance-related skills in cricket, cycling, running, and team sports (e.g., baseball, football, hockey, netball, soccer, tennis). Better neuromuscular control of postural and core stability contribute to more efficient functional movements specific to particular sports. Training programs incorporating general and sport-specific exercises that involve the use of postural and core muscles showed an improvement of body balance, back muscle strength, and endurance. However, there is controversy about whether the improvement in these abilities is translated into athletic performance. There is still a lack of research investigating the relationship of body balance and stability of the core with sport-specific performance. In particular, corresponding variables should be better specified in relation to functional movements in sports with high demands on postural and core stability. Identifying the relationship of passive, active, and neural mechanisms underlying balance control and spinal posture with athlete performance would provide a basis for a multifaced approach in designing training and testing tools addressing postural and core stability in athletes under sport-specific conditions.
... Several studies have shown that the stability and resistance of this complex can lead to greater performance of the torso on the saddle, which contributes to the optimizing of lower extremities' mechanics during pedaling 5,6 . Fatigue alters lumbopelvic-hip stability in high intensity cycling 6,7 , and this can lead to poor lumbopelvic-hip complex stability, and thereby to poor alignment of lower extremities during pedaling or a deficit in the transfer or force applied to pedals 5 . ...
... Several studies have shown that the stability and resistance of this complex can lead to greater performance of the torso on the saddle, which contributes to the optimizing of lower extremities' mechanics during pedaling 5,6 . Fatigue alters lumbopelvic-hip stability in high intensity cycling 6,7 , and this can lead to poor lumbopelvic-hip complex stability, and thereby to poor alignment of lower extremities during pedaling or a deficit in the transfer or force applied to pedals 5 . ...
... Kinematic evaluation has been implemented as well, through biomechanical motion capture systems, showing high reliability values (ICC=0.84-0.96) 5,11,12 . Finally, the ROM has been analyzed through different electronic devices such as the Spinal Mouse (ICC=0.84-0.97) 4 , 13 or BodyGuard (ICC≥0.97) ...
Objectives: The purpose of the present study is to assess the effects of an intense cycling training session on the stability
of the lumbopelvic-hip complex through two dynamic exercise tests - the single-leg-deadlift (SLD) and a variation of the
bird-modified dog (BD), via the OCTOcore application. Methods: Thirty-one elite female road cyclists were self-evaluated
with her owns smartphones, before and immediately after finishing their training sessions. Right, left and composite were
measured for each exercise test. Results: There was a significant time effect on performance for both the SLB and BD tests
(p<0.05; η2=0.137), and the SLD and BD tests were increased with respect to the pre-test at 15% and 17%, respectively.
Conclusion: An intense cycling training session produced significant alterations in lumbopelvic behavior in the elite female
cyclists. The OCTOcore application demonstrated that it was a sensitive tool in detecting these changes and it could easily
be used by the cyclists themselves.
... The musculature positioning of the core enables the maintenance of a neutral position of the spine and pelvis, functioning in such a way as to protect against injuries to these parts of the body (Stanton, Reaburn, & Humphries, 2004). However, some researchers have found different relationships between core stability (Abt et al., 2007;Nesser, Huxel, Tincher, & Okada, 2008;Nesser & Lee, 2009) and programs related to the development of core stability (Stanton et al., 2004;Tse, McManus, & Masters, 2005;Myer et al., 2006;Thompson, Cobb, & Blackwell, 2007). The core muscles are thought to play a significant role in the transfer of kinetic energy across the trunk to the extremities (Abt et al., 2007;Tse et al., 2005). ...
... However, some researchers have found different relationships between core stability (Abt et al., 2007;Nesser, Huxel, Tincher, & Okada, 2008;Nesser & Lee, 2009) and programs related to the development of core stability (Stanton et al., 2004;Tse, McManus, & Masters, 2005;Myer et al., 2006;Thompson, Cobb, & Blackwell, 2007). The core muscles are thought to play a significant role in the transfer of kinetic energy across the trunk to the extremities (Abt et al., 2007;Tse et al., 2005). Sports performance can be significantly reduced if the extremity muscles are allowed to be much stronger than the core muscles (Tse et al, 2005;Nesser et al., 2008;Nesser & Lee, 2009). ...
... Some research has examined the link between core stability in different sports. The aim was to assess the role of the core in sports performance (Abt et al., 2007;Nesser et al., 2008;Nesser & Lee, 2009). Some other research has considered the economy/performance ratio (Stanton et al., 2004), the speed of movement of the rod head in golfers (Thompson et al., 2007), swimming (Nikolenko, Brown, Coburn, Spiering, & Tran, 2011), rowing (Tse et al., 2005) and balance (Myer et al., 2006). ...
The aim of this research is to investigate existing research dealing with the topic of the structure, functional and morphological status of the muscles that make up the body's core, as well as how improving the core affects the advancement of sports technique and its efficiency. The term core most commonly refers to the trunk, or more precisely, to the lumbar region. Core muscles play a significant role in lower limb alignment and stability, associated with poor alignment and injuries. The development of the core strength to improve the efficiency of sports performance is a controversial issue that has yielded different results. The analysis of the scientific journal articles revealed that the specificity of the program for increasing lumbar stabilization with the appropriate sport or skill is of the utmost importance. Therefore, it is necessary to specialize in training facilities so that they are suited to a specific sports branch or discipline.
... Some researchers have induced fatigue in core muscles using an Isokinetic Machine [14], that is both costly and not easily accessible. Also this instrument does not provide functional movements similar to the activities of daily living or sports, and it induces fatigue only in specific muscles in each trial while the core comprises a rather large group of muscles. ...
... Also this instrument does not provide functional movements similar to the activities of daily living or sports, and it induces fatigue only in specific muscles in each trial while the core comprises a rather large group of muscles. To our knowledge, only one research group has designed a functional protocol to fatigue the core [14]. However, this protocol has not been explained in a clear and detailed way which makes it non-replicable for other researchers. ...
... The flowchart ( Figure 1) depicts visually the procedures in the first phase of the study which was intended to produce core muscle fatigue. The FCFP was developed from Abt and colleague's Core Fatigue Workout [14]. It consisted of six exercises ( Figure 2) lasting 24 min with four consecutive sets. ...
Background: Core stability, i.e. the ability to control the position and motion of the body’s core has been proposed to be an important factor involved in postural sway. Muscle fatigue may adversely affect the function of core muscles. Although many studies have
investigated effects of core muscle fatigue on balance, mostly non-standard fatigue protocols have been used which can potentially call into question the validity of their results.
Purpose: This paper contributes to the existing literature by developing a standard functional core fatigue protocol (FCFP) to functionally induce fatigue in all core muscles, and to examine its effects on postural sway in collegiate female athletes.
Method: The endurance of core muscles and postural sway was assessed in sixty female collegiate athletes using the Pressure Biofeedback Unit (PBU) and the Force Distribution Measurement-Small multifunction force-measuring plate, respectively. The confidence interval was set at 95% (p < 0.05).
Results: A significant decrease in endurance of core muscles was found in the experimental group after their participation in the FCFP (p < 0.001). Also, the displacement of the centre of pressure in both ‘path length’ and ‘area’ as indices of postural sway significantly increased compared to the related pre-fatigue values
(p < 0.001).
Conclusion: The designed FCFP can induce fatigue in core muscles efficiently and has significant negative effects on postural sway in collegiate female athletes.
... In addition to the posture adopted by the cyclist on the bicycle, another characteristic of cycling is the need to maintain balance and generate power on the pedals in order to displace the bicycle [28], where the trunk angle influences muscle recruitment and intermuscular dynamics in the lower limbs [29]. In this regard, core stability is crucial in efficiently transferring power from the lower to the upper body and vice versa and maintaining proper body position for more extended periods [30]. ...
... However, there were no statistical differences for upper and middle trapezius fibers, erector spinae, and anterior rectus abdominis. In this regard, Abt et al. [28] reported that core stability contributes to lower extremity cycling mechanics. These improvements in core strength could promote greater torso stability within the saddle and maintain lower extremity alignment to apply greater force transmission to the pedals. ...
(1) Background: Cycling is characterized by a sustained sitting posture on the bicycle, where physiologic spinal curvatures are modified from standing to cycling. Therefore, the main objective was to evaluate and compare the morphology of the spine and the core muscle activity in standing posture and cycling at low intensity. (2) Methods: Twelve competitive cyclists participated in the study. Spinal morphology was evaluated using an infrared-camera system. Muscle activation was recorded using a surface electromyography device. (3) Conclusions: The lumbar spine changes its morphology from lordosis in standing to kyphosis (lumbar flexion) when pedaling on the bicycle. The sacral tilt significantly increases its anterior tilt when cycling compared to when standing. The spinal morphology and sacral tilt are dynamic depending on the pedal’s position during the pedal stroke quadrants. The infraspinatus, latissimus dorsi, external oblique, and pectoralis major showed significantly higher activation pedaling than when standing, although with very low values.
... Moreover, core stability has received considerable attention in the sports field, attributing improvements in performance and injury prevention (Akuthota et al., 2008). Specifically, in cycling, the stability of the core contributes to improving the mechanics of the lower limbs, transmitting greater force on the pedals and increasing the stability of the trunk on the saddle (Abt et al., 2007). Therefore, several studies have evaluated the electromyographic activity of the trunk muscles in cycling (Brand et al., 2020;Juker et al., 1998;Usabiaga et al., 1997). ...
... This increase in muscle activation is possibly due to the need to stabilise the trunk since other studies have found a significant decrease in postural stability as the intensity of effort increases (Rannama et al., 2017) or the need to generate and transmit a greater force in the pedals as the pedalling resistance increases. In this line, Abt et al. (2007) reported that core stability improves lower limb mechanics in cycling. In addition, other studies have observed greater muscle activity in the lower limbs at the highest intensities of a maximal cycling test (Holliday et al., 2019;. ...
Cycling is a sport where cyclists predominantly adopt a sitting posture, with the trunk tilted forward. This posture requires a high volume of training and duration in several intensities of effort. This study aims to: 1) evaluate the behaviour of the thoracic and lumbar spine flexion and sacral inclination in the sagittal plane, the thoracic and lumbar spine flexion in the frontal plane, and the trunk torsion in the transverse plane; 2) compare the activation of the core muscles as the intensity of effort increases during an incremental test in cycling, and 3) identify which core muscle has a greater activation in each intensity zone. The spinal posture and the activation of the eight core muscles were evaluated in twelve competitive cyclists during incremental cycling intensities. Thoracic and lum-bar spine flexion and sacral inclination statistically increased as the intensity of effort increased (Start < VT1 < VT2 < VO2max). A significant increase in muscle activation was observed in all core muscles evaluated as the intensity increased. The rectus abdominis showed statistically significant greater muscle activation than the other core muscles evaluated. In conclusion, as the intensity of effort in cycling increases, cyclists significantly increase the thoracic and lumbar spine flexion, the sacral inclination in the sagittal plane, the thoracic and lumbar spine flexion in the frontal plane, trunk rotation in the transverse plane, as well as the activation of the core muscles.
... Cycling is a sport in which the athlete transmits force to the pedals, while maintaining a position of lumbar and thoracic flexion 6 . Several studies have shown that the lumbopelvic complex stability and strength lead to greater control of trunk on the saddle, which optimizes the mechanics of the lower extremities and the control of the transfer of the force applied to the pedals 7,8 . ...
... Previous studies indicated that cyclist with low central stability in Functional Movement Screen (FMS) test moved their bodies more on the saddle 35 , and that could affect the optimizing of lower extremities' mechanics during pedaling 7,8 . Moreover, the fatigue of the lumbopelvic complex causes alterations in kinematic variables during pedaling 7 . ...
Objectives: The purpose of this study was to determine the effects of short-term lumbopelvic stability training on muscular endurance and stability in elite female cyclists. Methods: Twenty-four female road cyclists were randomly allocated to a core training group (CTG, n=12) or control group (CG, n=12). In addition to their scheduled training the CTG performed a core training program, that consisted of 6 core exercises performed in a session every other day until a total of 8 training sessions were completed. The CG did not receive the core training program and completed their scheduled
training. The lumbopelvic-hip complex was assessed pre- and post-core program included the following exercises: single
leg deadlift (SLD), bird-dog (BD), plank test (PT), and side-bridge plank test (SPT). Results: In comparison to CG, CTG
significantly improved the time to failure in PT, SPT-Left, and SPT-Right (p<0.05). Further, CTG resulted in a significant decrease in SLD (p<0.05) compared to CG for the three accelerometry measures. Conclusion: The present results indicate that following 8 sessions of lumbopelvic stability training muscular endurance and core stability were enhanced.
... Abt and colleagues' trunk muscles fatigue protocol was used to fatiguing the trunk muscles in all movement plates (Abt et al. 2007). This protocol proven reliability and centrality in trunk muscles fatigue has been demonstrated by Abt's isokinetic strength test (Abt et al. 2007) that could fatigue trunk muscles. ...
... Abt and colleagues' trunk muscles fatigue protocol was used to fatiguing the trunk muscles in all movement plates (Abt et al. 2007). This protocol proven reliability and centrality in trunk muscles fatigue has been demonstrated by Abt's isokinetic strength test (Abt et al. 2007) that could fatigue trunk muscles. The protocol lasted for 32 min and consisted of four consecutive cycles of seven exercises, so that the subject performed each exercise for 20 repetition in 40 s (each repetition in two seconds) and rested for 20 s between two different exercises. ...
During running, trunk muscles act to sufficiently contribute to the energy generation and transmission of the body parts. Improper function of trunk muscles affects running mechanics adversely and could result in altered lower limb energetics. The aim of this study was to examine the effects of trunk muscles fatigue on plantar pressure distribution in novice runners. 46 novice heel-to-toe runners (26 female and 20 male) ran in 3.3 m/s before and after the trunk muscles fatigue along the plantar pressure measuring device. Then, participants performed trunk muscles fatigue protocol. Trunk muscles fatigue protocol consisted of four consecutive cycles of seven exercises (1) rotating trunk with a medicine ball in sitting position, 2) prone static torso extension with a medicine ball, 3) rotate lower torso with a medicine ball in supine position, 4) incline sit-ups with a weight plate, 5) lateral side binding with a weight plate, 6) rotating lumbar extension with weighted plate, and 7) standing trunk rotation with weighted pulley resistant. After trunk muscles fatigue, increases in loading of lesser toes (p=0.001, ES=0.379), fourth (p=0.001, ES=0.474) and fifth metatarsals (p=0.004, ES=0.173) and medial and lateral heel (p=0.018,0.001, ES=0.118,0.427) were observed. Also, foot progression angle (p=0.001, ES=392) and relative time of initial contact phase (p=0.003, ES=0.182) decreased. The trunk muscles fatigue could alter the plantar pressure distribution pattern. Novice runners should consider strengthening of the trunk region muscles to avoid trunk muscles strength reduction-related changes in running mechanics.
... Previous biomechanical research has established the importance of the trunk to extremity function (1,2,20) and injury (12). Specifically, Abt et al. (1) identified fatigue of the core musculature altered lower extremity kinematics in cyclists. ...
... Previous biomechanical research has established the importance of the trunk to extremity function (1,2,20) and injury (12). Specifically, Abt et al. (1) identified fatigue of the core musculature altered lower extremity kinematics in cyclists. Likewise, Leetun et al. (12) identified core muscle weakness was associated with a higher likelihood of lower extremity injury. ...
Cacolice, PA, Carcia, CR, and Scibek, JS. Shoulder flexion torque is augmented by a volitional abdominal isometric contraction. J Strength Cond Res XX(X): 000-000, 2019-A stable core provides a solid base to facilitate effective extremity function. It is unclear whether an individual is able to produce a greater amount of upper extremity torque while performing a volitional core contraction when compared with the independent contraction that occurs subconsciously. Therefore, the purpose of this study was to determine whether peak shoulder flexion torque values were different with and without a concurrent volitional core isometric contraction. Thirty healthy, recreationally active college-aged students participated. Surface electromyography from the rectus abdominis (RA) was captured using a telemetry system interfaced with a software acquisition system and personal computer. In a counterbalanced alternating order, subjects completed 3 trials of maximal isometric shoulder flexion at 90˚with90˚with and without a volitional abdominal contraction. Percent activation of the RA was greater when subjects volitionally contracted their core (15.8 6 12.7%) compared with the subconscious contracted condition (6.3 6 4.8%) (p # 0.001). Isometric shoulder flexion peak torque was greater when the core was actively contracted (44.6 6 18.9 N 3 m) compared with when the core was recruited subconsciously (30.7 6 15.7 N 3 m) (p # 0.001). These findings suggest the clinician should encourage the individual to activate their core musculature when performing upper extremity strength activities.
... Prolonged flexion for up to 20 minutes was enough to shut down the EMG activity of the lumbar multifidus for up to 7 hours (Jackson M et al 2001). It is widely accepted that spinal stability is a crucial variable in lower extremity force output (Clair JM, et al 2009 Core strength and stability would be required to ensure cycling efficiency, in addition to contributing to the enhancement of the leverage from which cyclists generate power to the pedals (Asplund, C. Ross, M 2010 and Abt, J et al 2007). Core strengthening has become a global fitness trend that has filtered into world of sports medicine due to its numerous benefits, including improving athletic ability and preventing injury (Akuthota V, et al 2008). ...
... The findings of Abt et al., (2007), are supported by Asplund and Ross (2010) who also indicated that the strength of the abdominal muscles is vital in maintaining a stable pelvic position. It was suggested that strengthening of these muscles could lead to improved pedaling efficiency. ...
... 5 In addition to the muscles responsible for pedaling, several others, including paravertebral, abdominal, and upper limb muscles, require constant activation to maintain the position of the trunk, head, and upper segments during the act of pedaling. 8 Because it is a highly repetitive activity, cyclists are more prone to overuse injuries, be they acute or chronic. During an hour of activity, the cyclist can perform around 5,000 pedaling cycles. ...
Introduction
Low back pain is one of the most common complaints among cyclists. The disharmony of the cyclist-bike combination may be a predisposing factor. Bike Fit is a technique that aims to adjust the bike to the individual characteristics of the cyclist.
Objectives
To investigate the relationship between the cyclist’s position on the bicycle and the occurrence of complaints of low back pain.
Methods
Data obtained during Bike Fit from 62 amateur cyclists were used in the study. Cyclists were filmed during the act of pedaling on a stationary roller and image analysis was performed using Kinovea® software. Data related to complaints of low back pain and positioning on the bicycle were used in the Chi-Square test and binary logistic regression.
Results
The mean age was 38.06 ± 8.82 years, 87.7% of the sample was composed of men and low back pain was found in 40.3% (25/62) of the participants. Univariate analysis showed a positive correlation between low back pain and the following variables: ankle dorsiflexion angle (X²=6.947, p=0.014) and upper limb reach (X²=5.247; p=0.032). Binary logistic regression showed a positive association between reaching with the upper limbs and low back pain (r=2.728; p=0.002) and a negative association between knee advancement and low back pain (r= -2.281; p=0.007).
Conclusion
Cyclists with low back pain present changes in their position on the bicycle, which reinforces the importance of evaluating the cyclist/bike combination. However, it is not possible to state whether the positional changes observed in the study sample are causes or consequences of low back pain. Level of evidence: Level III; Cross-sectional observational study.
Keywords:
Bicycling; Low back pain; Ergonomics; Posture
... 5 Além dos músculos responsáveis pela pedalada, vários outros, incluindo, paravertebrais, abdominais e dos membros superiores, necessitam de constante ativação para manter a postura do tronco, cabeça e segmentos superiores durante o ato da pedalada. 8 Por ser uma atividade altamente repetitiva, os praticantes de ciclismo estão mais propensos a lesões por overuse, sejam elas agudas ou crônicas. Afinal, durante uma hora de atividade, o ciclista pode realizar cerca de 5000 ciclos de pedalada. ...
Introduction
Low back pain is one of the most common complaints among cyclists. The disharmony of the cyclist-bike combination may be a predisposing factor. Bike Fit is a technique that aims to adjust the bike to the individual characteristics of the cyclist.
Objectives
To investigate the relationship between the cyclist’s position on the bicycle and the occurrence of complaints of low back pain.
Methods
Data obtained during Bike Fit from 62 amateur cyclists were used in the study. Cyclists were filmed during the act of pedaling on a stationary roller and image analysis was performed using Kinovea® software. Data related to complaints of low back pain and positioning on the bicycle were used in the Chi-Square test and binary logistic regression.
Results
The mean age was 38.06 ± 8.82 years, 87.7% of the sample was composed of men and low back pain was found in 40.3% (25/62) of the participants. Univariate analysis showed a positive correlation between low back pain and the following variables: ankle dorsiflexion angle (X²=6.947, p=0.014) and upper limb reach (X²=5.247; p=0.032). Binary logistic regression showed a positive association between reaching with the upper limbs and low back pain (r=2.728; p=0.002) and a negative association between knee advancement and low back pain (r= -2.281; p=0.007).
Conclusion
Cyclists with low back pain present changes in their position on the bicycle, which reinforces the importance of evaluating the cyclist/bike combination. However, it is not possible to state whether the positional changes observed in the study sample are causes or consequences of low back pain. Level of evidence: Level III; Cross-sectional observational study.
Keywords:
Bicycling; Low back pain; Ergonomics; Posture
... Therefore, most current conditioning programs in schools also include exercises strengthening core musculature, in addition to traditional resistance exercises. Research so far has been aimed at investigations of the relationship between core stability and athletic performance, as well as the assessment of the effectiveness of core strengthening and stabilization exercises in children and adolescents [3][4][5][7][8][9][12][13][14][15][16][17][18]. Nevertheless, there are only a few studies dealing with young athletes. ...
This study investigates the effect of 12-week core strengthening and weight training on muscle strength, endurance and flexibility in school-aged athletes. Ninety male athletes at the age of 12 were randomly divided into three equal groups (30 in each). Group 1 underwent core strengthening training, group 2 underwent weight training, and group 3 was the control. The training was for 12 weeks, with three sessions per week (one hour per session). Prior to and after the training, abdominal strength, endurance, and flexibility were evaluated using the sit-ups test, the Cooper 12 min run test and the sit and reach test. The analysis of variance was used to analyze pre- and post-intervention data. The results showed that both the core strength training group and the weight training group significantly (p = 0.00) improved in abdominal strength, represented by the number of sit-ups (from 18.70 ± 3.20 to 22.21 ± 3.50 and from 17.60 ± 3.29 to 21.60 ± 3.63, respectively); endurance, represented by distance covered in 12 min (from 1817 ± 185.78 m to 2008.97 ± 214.79 m and from 1806 ± 237.25 m to 2002.59 ± 83.32 m, respectively); and flexibility, represented by the sit and reach distance (from 23.48 ± 2.75 cm to 25.96 ± 2.38 cm and from 23.66 ± 2.92 cm to 25.86 ± 2.55 cm, respectively) when compared to the control group (from 17.20 ± 3.20 to 16.39 ± 2.69; from 1813 ± 224.69 m to 1778.15 ± 05.28 m; from 23.46 ± 3.06 cm to 21.76 ± 2.56 cm). More specifically, abdominal strength and endurance improved slightly more in the weight training group than in the core strength training group, whilst flexibility increased slightly more in the core strength training group than in the weight training group. These findings indicate that both core strengthening training and weight training are effective in improving physical fitness in school-aged athletes; however, the improvement is to differing extents regarding their endurance, flexibility, and abdominal strength.
... When the stabilising role of the trunk is considered, reduced © Editorial Committee of Journal of Human Kinetics trunk lean can occur early as muscle fatigue can precede changes in trunk lean and trunk range of motion (Dingwell et al., 2008). Similarly, a significant compensatory effect on movement kinematics without alterations in pedalling would occur (Abt et al., 2007). Thus, it is possible that a similar attributable effect occurs through whole body acceleration of the CoM which may contribute to greater acceleration magnitudes and the RPE with a corresponding reduction in power. ...
Indoor spin cycling has gained popularity as a training modality for triathletes. Part of its appeal is that it can form a component of a structured periodised training program and provide an alternative to outdoor cycling. Indices of physiological components (i.e., the metabolic equivalent, caloric cost, perceived exertion) and changes in the body position can be inferred by wearable technology such as an accelerometer. This pilot study aimed to investigate the relationship between the rating of perceived exertion, heart rate reserve, and the metabolic equivalent between the whole body centre of mass acceleration using a sacrum mounted triaxial accelerometer during 20 minutes of 6 varied power conditions of indoor spin cycling. Compared with other conditions, cycling at a steady state (>152-205 W) resulted in extremely large effects (> 0.9) in mediolateral acceleration and the rating of perceived exertion (p < 0.0001). The relationship between the body position (aerodynamic to drops) induced significant changes in anteroposterior acceleration magnitude (p < 0.0001), although moving from drops to the aerodynamic position was not significant despite a large increase in heart rate reserve and extremely large effects of perceived exertion. The rating of perceived exertion scale and the metabolic equivalent comparative to the whole body centre of mass acceleration magnitude and power displayed a strong correlation (r = 0.865). An individually determined whole body centre of mass accelerations combined with perceived exertion, the metabolic equivalent and heart rate reserve could potentially contribute to improved indoor triathlete spin cycling performance.
... sobre o ciclista durante o esforço, onde um ciclista que demonstrava ter o core mais fortalecido conseguia manter-se mais estável durante esforço extremo e seu adversário sofria mais durante o esforço, apontando que o fortalecimento do core poderia ser um dos responsável pela diminuição de movimento na coluna assim também reduzindo a incidência de lesões lombares.3 Smoliga em seu estudo, evidencia que a queda de desempenho é causada pela fadiga da musculatura estabilizadora ou core, apontando significativa queda de potência e controle motor do tronco após sua fadiga.24 No estudo de sauer foi testado um protocolo de exercício para analisar o movimento do corpo humano durante certas potências exercidas.O estudo foi dividido entre homens e mulheres e foram colocados em testes de 100W, 150W e 200W na bicicleta ergométrica. ...
This article is about low back pain in road cyclist, a revision study based in 30 articles from all over the world
... In this instance, the capacity of the lumbar-pelvic-hip complex to essentially control lower trunk movement and maintain trunk stability and endurance can be compromised. As upper body stability provides the basis from which power is generated, 39 adequate trunk control affords greater control for upper and lower extremity motion and force development. Therefore, the core musculature may influence the kinematics and loadbearing capacity of the lower extremities by determining what loads are transmitted from the trunk. ...
Triathlon has been an Olympic sport since the 2000 Sydney Olympics and has developed rapidly, leading to variations in race categories. Although running after cycling necessitates a postural change from a non-weight-bearing activity to a weight bearing one, no study has quantified the magnitude of trunk acceleration during cycling in different seat positions and the consequential effect on running. Therefore, this study was conducted to evaluate the effectiveness of a triaxial accelerometer to determine acceleration magnitudes of the trunk in a 20 km outdoor cycling event in two seat positions that were immediately followed by a 5 km overground run. Interpretation of data was evaluated based on cadence changes while triathletes cycled in an aerodynamic position in two seat positions. Running data was evaluated based on sinusoidal curves and foot strike peaks. The evaluation of accelerometer derived data within a characteristic overground setting suggests that cycling in an adjusted seat position significantly reduced trunk acceleration in both longitudinal and mediolateral directions with large effects ( p < 0.0001, d > 0.9). A significant and large effect was found in both longitudinal and anteroposterior trunk acceleration in post-cycle running between seat positions ( d > 0.9, p < 0.0001). In the longitudinal direction, a significant reduction in trunk acceleration occurred when running after the seat was adjusted with participants completing the 5 km run faster (21:55 ± 3:17 min compared to 22:05 ± 2:53 min). The results suggest that when the seat position is adjusted based on individual anthropometrics, overall trunk acceleration magnitude is reduced in both cycling and running. Accessible and practical sensor technology could be beneficial for postural considerations in triathlons.
... Meanwhile, Individuals with lower back pain show various types of hip dysfunction, including reduced endurance and delayed activation of hip extension and abduction [8]. Poor trunk strength and control, as well as hip muscle function, are associated with risk factors for lower limb injury [9][10][11]. Although these findings indicate the importance of coordinated trunk and hip activity, few exercises simultaneously activate these muscles. ...
The importance of an interaction between trunk stability muscles and hip muscle function has been suggested. However, reported exercises rarely act on the trunk and hip muscles simultaneously. Here, we devised an abdominal oblique and hip muscle exercise, the Self-oblique exercise (SOE). We examined whether SOE activated abdominal and hip muscles in the supine and half-kneeling positions, compared with abdominal crunch (AC) and plank exercises; and whether participants could modulate the exercise load. Participants were 20 healthy males with some sports experience such as football and baseball on average 10.5 ± 4.0 years. Participants applied self-pressure to their right thighs using the contralateral upper limb with 40% or 70% of the maximum force in Supine SOE and Half- kneeling SOE. The following abdominal and hip muscles were measured using surface electromyography: bilateral external obliques (EO), bilateral internal obliques (IO), right rectus abdominis, right gluteus medius (GMed), and right adductor longus (ADD). All evaluated muscle groups showed significant differences between exercises (p < 0.001). Supine SOE-70% showed 80.4% maximal voluntary contraction (MVC) for left EO (p < 0.017), 61.4% MVC for right IO (p < 0.027), 24.3% MVC for GMed (p < 0.002), and 42.4% MVC for ADD (p < 0.004); these were significantly greatest among all exercises. Muscle activity during Supine SOE-70% was greater than that during Supine SOE-40%. Similarly, Half-kneeling SOE-40% promoted abdominal and hip muscle exertion, and showed more significant activity in GMed (p < 0.006) and ADD (p < 0.001) than AC and plank. SOE could activate abdominal and hip muscles depends on the pressure applied by upper limb. Also, SOE allows participants to modulate the exercise load in a self-controlled step by step manner. Modulation of the exercise load is difficult in AC or plank compared to SOE, and AC or plank cannot obtain simultaneous oblique and hip muscle activity. SOE could be practiced anywhere, in various positions, without any tools.
... Existing literature suggests differences regarding neuromuscular activation between unilateral and bilateral resistance exercise, induced by increased stability requirements and neuromuscular control during unilateral exercise (7,25,47). Abt et al. (4) suggested that a strong and stable core musculature may promote torso stabilization within the saddle and maintenance of lower extremity alignment, which may contribute to efficient force generation in the pedal stroke, in particular during prolonged cycling. ...
Ji, S, Donath, L, and Wahl, P. Effects of alternating unilateral vs. bilateral resistance training on sprint and endurance cycling performance in trained endurance athletes: A 3-armed, randomized, controlled, pilot trial. J Strength Cond Res XX(X): 000-000, 2021-Traditional preparatory resistance training for cyclists mainly relies on simultaneous bilateral movement patterns. This lack of movement specificity may impede transfer effects to specific aerobic and anaerobic requirements on the bike. Hence, this study investigated the effects of resistance training in alternating unilateral vs. simultaneous bilateral movement pattern on strength and anaerobic as well as aerobic cycling performance indices. Twenty-four trained triathletes and cyclists (age: 31.1 ± 8.1 years; V[Combining Dot Above]O2max: 57.6 ± 7.1 ml·min-1·kg-1) were randomly assigned to either an alternating unilateral (AUL), a simultaneous bilateral (BIL) training group or a control group (CON). Ten weeks of resistance training (4 × 4-10 repetition maximum) were completed by both training groups, although CON maintained their usual training regimen without resistance training. Maximal strength was tested during isometric leg extension, leg curl, and leg press in both unilateral and bilateral conditions. To compare the transfer effects of the training groups, determinants of cycling performance and time to exhaustion at 105% of the estimated anaerobic threshold were examined. Maximal leg strength notably increased in both training groups (BIL: ∼28%; AUL: ∼27%; p < 0.01) but not in CON (∼6%; p > 0.54). A significant improvement in cycling time trial performance was also observed in both training groups (AUL: 67%; BIL: 43%; p < 0.05) but not for CON (37%; p = 0.43). Bilateral group exhibited an improved cycling economy at submaximal intensities (∼8%; p < 0.05) but no changes occurred in AUL and CON (∼3%; p > 0.24). While sprint cycling performance decreased in CON (peak power: -6%; acceleration index: -15%; p < 0.05), improvement in favor of AUL was observed for acceleration abilities during maximal sprinting (20%; d = 0.5). Our pilot data underpin the importance of resistance training independent of its specific movement pattern both for improving the endurance cycling performance and maximal leg strength. Further research should corroborate our preliminary findings on whether sprint cycling benefits favorably from AUL resistance training.
... The ability to control muscles also decreases, with the greatest influence on maximum muscle strength, muscle power, and speed of movement [23]. When athletes experience abdominal muscle fatigue during competition or training, they are unable to transmit strength to the limbs steadily; this affects the stability of the core muscles and changes the movement style, which may increase the incidence of sports injuries [24]. Previous studies have reported that core-muscle training or abdominal-muscle training can effectively increase athletes' balance of movement or stabilize their limb strength [12,14,15,25]. ...
The aim of this study was to investigate the effects of rectus abdominis (RA) fatigue on the jumping performance and landing loads of volleyball players during countermovement jumps (CMJs) and spike jumps (SPJs). Twelve healthy university volleyball players were evaluated using a three-dimensional motion analysis system, force plates, and surface electromyography (EMG). The lowest center of mass (Min-CoM), maximum jumping height (Max-JH), angles of joints at take-off and landing, joint moment of the lower limbs, and EMG parameters of the RA, erector spinae, and lower limb muscles, when performing the CMJs and SPJs, were recorded before and after a 10 min RA muscle fatigue intervention. After RA fatigue, the Max-JH was significantly reduced, and the lowest Min-CoM was significantly increased. The take-off angles changed significantly at the ankle (SPJ), knee (CMJ), and hip (SPJ), and the plantar flexion torque changed significantly at the SPJ touchdown. The contribution ratio of the feet during SPJs and CMJs changed after fatigue. Temporary RA fatigue decreases the jump height of athletes and causes a change in the landing strategy.
... None of the studies assessed core strength of any kind. Hip weakness and poor trunk control have been implicated as risk factors in lower extremity injury 2,46,48,109 and associated with biomechanical deficits that are linked to second injury risk. 51,80 Clinically applicable assessments of hip and core strength are necessary to reach athletes in all settings. ...
Context:
There is a lack of consensus regarding test batteries for return to sport (RTS) after anterior cruciate ligament reconstruction (ACLR).
Objective:
To report the RTS test batteries for individuals after ACLR and to examine alignment with the American Academy of Orthopaedic Surgeons (AAOS) Appropriate Use Criteria (AUC). Finally, to examine how published RTS batteries prior to the AAOS AUC (2010-2015) compared with those after publication of the AUC (2016-2020).
Data source:
A systematic search of PubMed (2010-2020).
Study selection:
Studies were included if they were published from 2010 to 2020, patients underwent primary ACLR and were tested between 6 months and 2 years postoperatively and included a minimum of 2 assessments. Studies were excluded if patients were tested outside the designated time; had undergone a revision, contralateral, or multiligament injury; included healthy participants; were level 5 evidence or the study was a systematic review. A total of 1012 articles were reviewed and 63 met the criteria.
Study design:
Systematic review.
Level of evidence:
Level 4.
Data extraction:
Information regarding the RTS batteries and patient demographics were extracted from the included articles.
Results:
A total of 63 studies met the inclusion and exclusion criteria (22 from 2010-2015 and 41 from 2016-2020). The most common RTS batteries included the hop test, quadriceps strength test, and patient-reported outcome measures. No study met all 7 AUC; the most common criteria met were functional skills (98.4%), followed by confidence (22.2%), then range of motion and knee stability (20.6%).
Conclusion:
The test batteries in the current literature show high variability and a lack of essential components necessary for RTS. No study met the AUC guidelines, suggesting a disconnect between recommended guidelines and clinical practice. Test battery research has expanded over the past decade; however, standardized, clinically applicable batteries that encompass all criteria are needed.
... Future research should investigate the relationship of core stability/strength with consistency in the spine and lower body kinematics. According to Abt et al. [56], core stability reduces torso movement and lower body alignment, and this could reduce the risk of injury in cyclists. Asplund and Ross [57] suggested that greater core stability would reduce the risk of suffering a spine injury, and this could be achieved through training focused on the trunk, performing dynamic and/or static exercises. ...
Kinematic analysis of the cycling position is a determining factor in injury prevention and optimal performance. Fatigue caused by high volume training can alter the kinematics of the lower body and spinal structures, thus increasing the risk of chronic injury. However, very few studies have established relationships between fatigue and postural change, being these in 2D analysis or incremental intensity protocols. Therefore, this study aimed to perform a 3D kinematic analysis of pedaling technique in a stable power fatigue protocol 23 amateur cyclists (28.3 +- 8.4 years) participated in this study. For this purpose, 3D kinematics in hip, knee, ankle, and lumbar joints, and thorax and pelvis were collected at three separate times during the protocol. Kinematic differences at the beginning, middle, and end of the protocol were analyzed for all joints using one-dimensional statistical parametric mapping. Significant differences (p < 0.05) were found in all the joints studied, but not all of them occur in the same planes or the same phase of the cycle. Some of the changes produced, such as greater lumbar and thoracic flexion, greater thoracic and pelvic tilt, or greater hip adduction, could lead to chronic knee and lumbar injuries. Therefore, bike fitting protocols should be carried out in fatigue situations to detect risk factor situations.
... According to the results of our study, the planar assumption sometimes used in the literature (e.g., Fregly and Zajac, 1995;Bini et al., 2013) may be questionable in the light of significant modifications for some anatomical rotations out of the sagittal plane. Those joint rotations may be harmful to the physical integrity of cyclists (Ruby et al., 1992;Bailey et al., 2003;Abt et al., 2007). In particular, some authors suggested that DOF out of the sagittal plane may be a cause of overuse injuries (Bailey et al., 2003;Gregersen and Hull, 2003;Pouliquen et al., 2018). ...
This study aimed to quantify the influence of an increase in power output (PO) on joint kinematics and electromyographic (EMG) activity during an incremental test to exhaustion for a population of professional cyclists. The hip flexion/extension and internal/external rotation as well as knee abduction/adduction ranges of motion were significantly decreased at 100% of the maximal aerobic power (MAP). EMG analysis revealed a significant increase in the root mean square (RMS) for all muscles from 70% of the MAP. Gastrocnemius muscles [lateralis gastrocnemius ( GasL ) and medialis gastrocnemius ( GasM )] were the less affected by the increase of PO. Cross-correlation method showed a significant increase in the lag angle values for VM in the last stage compared to the first stage, meaning that the onset of the activation started earlier during the pedaling cycle. Statistical Parametric Mapping (SPM) demonstrated that from 70% MAP, biceps femoris ( BF ), tibialis anterior ( TA ), gluteus maximus ( GM ), and rectus femoris ( RF ) yielded larger ranges of the crank cycle on which the level of recruitment was significantly increased. This study revealed specific muscular and kinematic coordination for professional cyclists in response to PO increase.
... To confirm this, there are indications that intensive cycling causes fatigue in muscles used for postural stabilisation [14]. This has led to suggestions that core strength training improves trunk stability on the saddle in order to maintain lower extremity alignment for greater effective force transmission to the pedals [37]. This advocates a need for greater upper body stabilisation when cycling, in agreement with McDaniel et al. [15] given that this extends to not only cope with the increased workload but also to balance the bike. ...
In the multisport of triathlon cycling is the longest of the three sequential disciplines. Triathlon bicycles differ from road bicycles with steeper seat tube angles with a change to saddle height altering the seat tube angle. This study evaluated the effectiveness of a tri axial accelerometer to determine acceleration magnitudes of the trunk in outdoor cycling in two saddle positions. Interpretation of data was evaluated based on cadence changes whilst triathletes cycled in an aerodynamic position in two saddle positions. The evaluation of accelerometer derived data within a characteristic overground setting suggests a significant reduction in mediolateral acceleration of the trunk, yielding a 25.1% decrease when saddle height was altered alongside reduced rate of perceived exertion (3.9%). Minimal differences were observed in anteroposterior and longitudinal acceleration. Evaluation of sensor data revealed a polynomial expression of the subtle changes between both saddle positions. This study shows that a triaxial accelerometer has capability to continuously measure acceleration magnitude of trunk movements during an in-the-field, varied cadence cycle protocol. Accessible and practical sensor technology could be relevant for postural considerations when exploring saddle position in dynamic settings.
... Some authors have documented the relationship between measures of core muscle strength and athlete performance [10,11], whereas others have not [12][13][14]. The relationship between the limbs and core muscles has been demonstrated for various lifting tasks, forehand and backhand strokes in tennis, overhead throwing in baseball and so forth [15][16][17][18][19][20][21]. These findings highlight the importance of core musculature in the transfer of momentum and torque throughout the kinetic chain during sport-specific tasks [4]. ...
This study investigates differences in power and velocity at different loads and power and force at different velocities during trunk rotations in athletes who practice sports with rotational demands on the trunk. Athletes of combat (n = 23), fighting (n = 39), ball (n = 52) and water sports (n = 19) with a mean age of 23.8 ± 1.5 years performed standing trunk rotations on each side with bars of different weights (from 1 kg up to 50 kg) placed on their shoulders. The findings showed significant between-group differences in mean power in the acceleration phase of trunk rotations, especially at higher weights (≥10.5 kg) or lower velocities (≤334.2 rad/s). The power at 10.5 kg was significantly higher in fighting than water (p = 0.035; d = 0.86), combat (p = 0.001; d = 1.53) and ball sports athletes (p = 0.001; d = 1.48), with no significant differences between the two latter groups; at 15.5 kg, it was higher in water than combat (p = 0.027; d = 0.91) and ball sports athletes (p = 0.009; d = 1.17) but not those in fighting sports; and at 20 kg, it was higher in water than combat (p = 0.013; d = 0.98) and ball sports athletes (p = 0.006; d = 1.33), with no significant differences with those in fighting sports. This testing is sensitive in discriminating between athletes of various sports, which may reflect the specificity of their training, including trunk rotations at various velocities under different load conditions.
... T he core is commonly defined in the research literature as ''lumbopelvic hip'' segments 1 but regularly includes structures that extend into the thigh (gluteal muscles), thoracic vertebrae (rectus abdominis and iliopsoas) and even the cervical vertebrae (multifidus). [1][2][3][4] Introducing the Core: Demystifying the Body of an Athlete offers a compelling rationale for including the thigh musculature and thoracic segments in the definition of the core on the basis of function and structural balance. The rationale is further supported with unique and effective models (eg, a baseball as the pubis symphysis in a harness model). ...
... Other possible causes may be that: the saddle height is not correct, the handlebar is too low, the crank length is too long, or simply due to poor coordination and posture control [45]. The greater alignment of the lower extremities increases the fatigue resistance of the cyclist and increases the output power [46]. ...
In this research, the performance and movements of amateur and professional cyclists were analyzed. For this, reflective markers have been used on different parts of the body of the participants in conjunction with sports cameras and a mobile power meter. The trajectories of the markers have been obtained with the software Kinovea and subsequently analyzed using error ellipses. It is demonstrated that the error ellipses help determine movement patterns in the knees, back, and hip. The covariance of the error ellipses can be indicative of the alignment and symmetry of the frontal movement of the knees. In addition, it allows verifying the alignment of the spine and the symmetry of the hip. Finally, it is shown that it is necessary to consider the uncertainty of the power devices since it considerably affects the evaluation of the cyclists’ performance. Devices with high uncertainty will demand a greater effort from the cyclist to meet the power required in the endurance test developed. The statistical magnitudes considered help to analyze power and evaluate the cyclists’ performance.
... This shares similarities with prior findings. Abt et al. (2007) detected that fatiguing trunk muscles have significant compensatory effect on cyclist movement kinematics without alterations in pedalling. Although pedalling technique was not monitored, RPE was checked at regular intervals to monitor the onset of fatigue since a change in trunk lean can occur early in the fatigue process. ...
This pilot study aimed to quantify the change of CoM acceleration when the trunk position and the power output was varied during indoor cycling. Triathletes (n=4) performed a varied indoor cycling power protocol in their natural training environment whilst wearing a trunk (sacrum) mounted wearable device containing a triaxial accelerometer. Mediolateral acceleration increased 26% as athletes moved from the drops position, to the aerodynamic position and back to the drops position. Although longitudinal acceleration increased 8%, minimal differences in anteroposterior CoM magnitude were observed. Power output was found to have an effect on both the mediolateral and longitudinal acceleration alongside increases in RPE. The results indicate that accelerometers may be effective in monitoring changes to trunk position and power output.
... Some previous studies showed close relations between anaerobic power and isokinetic knee strength (Loveless et al., 2005). According to Abt et al. (2007), the efficiency of core strength, quadriceps, and hamstring leads positive effects to padding and racing performance (da Silva et al., 2016). Not only the hamstring and quadriceps ratio of knee muscles is the factors that determine the victory (Brughelli et al., 2010;McIntyre et al., 2012) but also the improvement of muscle strength and the maximum power contributes to shorten cycling records to cyclists (Bentley et al., 2001;Koninckx et al., 2010). ...
The purpose of this study is to compare and analyze the difference of isokinetic muscle functions, anaerobic capabilities, pedaling power and maximum strength according to race-class of Korea racing cyclists. The participants in this study were 57 racing cyclist candidates who graduated from the Korea racing school. One year after graduation, we confirmed race-class of candidates and they were divided into three groups: the first-class racer group (FC, n=14), second-class racer group (SC, n=29), third-class racer group (TC, n=14). The isokinetic muscle strength of trunk and knee flexion/extension was measured using HUMAC NORM and basic physical strength such as squat and bench press was analyzed by Ariel device. As results of this study, % Fat (percentage of body fat) in FC group was the lowest compared to other groups. Isokinetic knee flexion strength was higher in FC group than SC and TC racer groups. Peak and average pedaling power as well as maximum muscle strength were significantly higher in FC group than in other groups. Our findings suggest new evidence that pedaling power and isokinetic muscle strength might be closely associated with race-class of Korea racing cyclists.
... Verimli bir hareketin gerçekleştirilmesinde eklem stabilitesi oldukça önemlidir. Merkez bölgesindeki stabilitenin azalması ise bireyin biyomekaniğinin bozulmasına neden olur 1 . Gelişmiş bir biyomekaniğin, atletik performansın yükselmesindeki etkenlerden olduğu bilinmektedir 21 . ...
Z Bu çalışma tenisçilerde Fonksiyonel Hareket Taraması (FHT) test skorları ile atletik performans ve servis atış hızı arasındaki ilişkiyi incelemek amacıyla yapılmıştır. Çalışmaya 13-15 yaş arasında 18 lisanslı tenisçi gönüllü olarak katılmıştır. Katılımcıların fonksiyonel hareketleri FHT test kitiyle, servis atış hızları radar cihazıyla, atletik performansları 20 m sürat, dikey ve yatay sıçrama, sağlık topu fırlatma ve spider testleriyle belirlenmiştir. Katılımcıların FHT test skorları ile atletik performans ve servis hızı arasındaki ilişkinin belirlenmesinde Spearman Korelasyon Analizi kullanılmıştır. Yapılan çalışmanın sonucunda FHT testi toplam skoru ile atletik performans ve servis hızı arasında istatistiksel olarak anlamlı bir ilişki belirlenmemiştir (p<0,05). FHT alt testlerinden gövde stabilite şınavı ile dikey sıçrama, yatay sıçrama, sağlık topu fırlatma ve servis atış hızı değişkenleri arasında pozitif yönlü bir ilişki belirlenirken, FHT alt testlerinden gövde stabilite şınavı ile spider ve 20 m sürat değişkenlerinde ise negatif yönlü anlamlı ilişki tespit edilmiştir (p<0.05). Katılımcıların FHT test toplam skorlarının (16,05 puan) yaralanma ihtimalini belirten kritik sınırının (14 puan) üzerinde olduğu belirlenmiştir. Sonuç olarak FHT testi ile atletik performans ve servis hızı arasındaki ilişki hipotezi doğrulanmamıştır. Bu durum FHT testi, fonksiyonel hareket kalıplarının uygunluğunu incelerken atletik performans testleri, hareketlerin en yüksek verimde yapılmasını incelemesiyle açıklanabilir. ABSTRACT This study was carried out in order to examine the relation between Fonctional Movement Screen test scores and atletic performance and service speed. 18 tennis players aged 13-15 participated in study voluntarily. Fonctional movement of the participant were evaluated with FMS test kit, service speeds with a radar kit, atletic performances with 20 meters test of speed, vertical and horizantal jumping, thorowing healt ball and spider test. In evaluating the relation between FMS test scores and atletics performance and service speed, Spearman Corelation Analyze was used. In the result of the study that was carried out between FMS test total scores and atletics performance and service speed no meaningful relation was statistically found (p>0.05). While a positive relation was determineted between body stability push up and the factors of vertical jump, horizontal jump, thoriwing healt ball, in FMS sub test a negative meaningful relation was determined between body stability push up and the factors of spider and 20 meter speed (p<0.005). It was determined that FMS test total scores (16.05 point) of the participants is evaluated to be over the critical level (14 point) that remarks the possibility injuring. As a result the hipothesis of the relation between FMS test and atletics performance and service speed couldn't be verified. The case can be explained with that while FMS test examines conformity of functional movement patterns, atletics performance test examines whether the movements are done at the highest efficiency.
Background and Objectives: Genu recurvatum deformity shifts the mechanical axis of lower extremity posteriorly which may disturb the balance and stability. The goal of this study was to compare the balance and core stability of female students with and without genu recurvatum.
Methods: 50 female middle school students (25 with genu recurvatum, mean age 14.88 ±0.6 and 25 without genu recurvatum mean age 15±0) from among the available samples were selected. The criteria for genu recurvatum were a 5-degree knee hyperextension. To measure static and dynamic balance we used stork balance test and Y test and to measure core stability we used Sorenson, plank, side plank and 60 degree sitting tests. Statistical analysis was done with SPSS software version 23. To compare the mean performance of the groups, independent t test and Mann–Whitney U test were used.
Results: Data analysis showed that the static (0/006, 0/001 dominant and non-dominant leg respectively) and dynamic (0/002, 0/002 dominant and non-dominant leg respectively) balance and core stability (0/007, 0/014, 0/007, 0/001 Sorenson, plank, side plank and 60-degree sitting tests respectively) of students without genu recurvatum were significantly better than those of students with genu recurvatum.
Conclusion: the results of present study showed that female teenagers with genu recurvatum have poor balance and core stability relative to female teenagers without genu recurvatum. Therefore, it is necessary to consider preventive and corrective training programs for those with genu recurvatum.
Key words: genu recurvatum, Core stability, Static balance, Dynamic balance
Background and Objective: Multiple sclerosis (MS) is one of the most common diseases in the central nervous system, caused by damage to myelin sheath. This study was done to compare the effect of eight weeks of core stabilization, theraband resistance and combined training on functional endurance and postural control in male patients with MS.
Methods: In this quasi-experimental study, 40 male patients with MS were non- randomly divided into three experimental and one control groups (each group, n = 10, age range 25 to 35 years, BMI between 20 and 25, and physical disability scale of 1 to 5.4). Core stabilization, theraband resistance and combined training, balance berg test and 6-minute walk test were performed in order to exercise protocols.
Results: Capacity movement and postural control were significantly improved in experimental groups in comparison with control group (P<0.05). The most variability was related to the combination of training program.
Conclusion: Eight weeks of core stabilization, theraband resistance and combined training improves functional endurance and postural control in men with MS.
Keywords: Multiple sclerosis, Core stabilization, Theraband resistance, Functional Endurance, Postural control
Context:
Comfort and pain in cyclists are often discussed as a result of the posture on the bike, and bike fit, including motion analysis, is advocated as a strategy to minimize these conditions. The relationship between cycling kinematics, comfort, and pain is still debatable.
Objectives:
To investigate the association of ankle, knee, and trunk kinematics with the occurrence of anterior knee pain (AKP) in mountain bike cyclists.
Design:
Cross-sectional study.
Methods:
Fifty cross-country mountain bike cyclists (26 with AKP and 24 without AKP) had their pedaling kinematics assessed. Linear and angular data from trunk, hip, knee, ankle, and foot from cyclists with and without AKP were recorded using Retül motion analysis system.
Results:
The binary logistic regression model showed that kinematic variables such as peak ankle plantar flexion, peak knee flexion, and forward trunk lean were significant predictors of AKP. Both larger peak plantar flexion and knee flexion decreased the probability of reporting AKP. On the other hand, larger forward trunk lean increased the probability of reporting AKP.
Conclusions:
Ankle, knee, and trunk sagittal kinematics may predict AKP in cross-country mountain bike cyclists, whereas hip, knee, and ankle alignment in the frontal plane showed no association with occurrence of AKP. In other words, cyclists with larger ankle plantar flexion and knee flexion are less likely to have AKP, whereas those with increased trunk forward lean are more likely to have AKP.
Recreational cycling is sort of sport that requires a decent level of endurance, and cyclists’ riding is determined by several physical abilities, in which muscular strength in upper limb is equally important as the lower limbs. While riding a bicycle, the hand grip turns out to be especially crucial not just for performance and the ability to remain upright in difficult situations and uneven surfaces but also for even moderate endurance and comfort of the rider A total of 60 recreational cyclists, 25-35 years old were included in the study. Grip strength of dominant and non-dominant hand was checked with Jamar hand held dynamometer pre cycling and was checked again after the 20km ride. Normality was checked and Dominant hand data passed the normality test thus, paired t-test was used to determine significance for (p<0.05). For Non-dominant hand readings didn’t support normality to the optimal level (p>0.05) hence non-parametric Wilcoxon signed test was used to determine significance as the samples were dependent. Mann-Whitney test was used to determine significance in Dominant and Non-Dominant hand pre cycling activity as well as comparison of Dominant and Non-Dominant hand post cycling activity, as data was not normally distributed and the samples were independent. (p>0.05). Results showed that there is significant difference in dominant as well as non-dominant hand pre and post riding activity with post cycling grip strength being reduced in both Dominant and Non-Dominant hand than the pre-cycling grip strength. Also, Dominant hand grip strength was more than the non-Dominant hand in both pre and post cycling. Key words: Recreational cyclists, Grip strength, dominant and non-dominant hand, Jamar hand held dynamometer.
In dit artikel gaan we in op wat er in de wetenschap bekend is over de meest voorkomende overbelastingsblessures bij wielrenners, welke invloed de afstelling van de fiets hierop kan hebben en welke preventieve oefenvormen je kunt uitvoeren.
Objective
To investigate the association of interactions among trunk, hip, and foot/ankle musculoskeletal factors with the presence of anterior knee pain (AKP) in mountain bikers.
Design
Cross-sectional study.
Setting
Private clinical setting.
Participants
Fifty professional and amateur cyclists, with and without AKP, were included.
Main outcome measures
Bridge test with unilateral knee extension, hip stability isometric test (HipSIT), passive hip internal rotation (IR) range of motion (ROM), shank-forefoot alignment (SFA), and ankle dorsiflexion ROM were analyzed by classification and regression tree (CART) to identify interactions with AKP presence. A receiver-operating characteristic (ROC) curve verified accuracy of the model. To investigate strength of associations, prevalence ratios were calculated for each terminal node of the CART model.
Results
Interactions among passive hip IR ROM, HipSIT, ankle dorsiflexion ROM and SFA identified mountain bikers with and without AKP. The model achieved 76.9% sensitivity and 87.5% specificity. The area under the ROC curve was 0.86 (95% confidence interval: 0.75–0.97; standard error 0.05; p < 0.0001).
Conclusion
Presence of AKP in mountain bike cyclists was associated with interactions among passive hip IR ROM, HipSIT and ankle dorsiflexion ROM captured by CART, indicating that the contribution of one factor depends on the presence of other factors.
Cycling is popular internationally as a mode of transport and sport. Cyclists often report sensory and motor changes in the hands during rides. In the past, assessment of these symptoms was based on clinical history, physical examination and neurophysiology. The aim of this narrative review was to evaluate existing publications and determine if there are areas for further improvement in the clinical setting.
Methods:
Searches were undertaken in accordance with the PRISMA guidelines using four online databases: PUBMED, OVID, CINAHL and WEB OF SCIENCE. Articles were evaluated using adapted versions of guidelines for case and cohort studies.
Results:
2630 articles were found and 13 were included in the review. 2 considered median, 9 considered ulnar and 2 assessed both nerves. 11 were case and 2 were cohort studies. 7 discussed neurophysiology and 1 mentioned ultrasound as a modality of investigation. Interventions were described in 3 articles.
Conclusion:
The quality of evidence is generally low when considering this problem. Clinical assessment and neurophysiology are commonly regarded as the method for assessing nerve symptoms amongst cyclists. Advances in musculoskeletal ultrasound add to our early investigative repertoire and may help expedite management and limit future disability. In addition, further research is required into screening and preventative measures amongst cyclists.
Aim: Muscle activity analysis during deadlift is an important tool for assessing the effectivity of the exercise. Some studies indicate difference in muscle activities when collegiate athletes perform it on unstable surface. Materials and
Methods: In this study, thirty collegiate male athletes were recruited. MVIC was recorded for each deadlift exercise.
Results: Isometric deadlift executed on BOSU ball resulted in greater % MVIC change in core muscles (p<0.05), i.e., transversus abdominis and multifidus while no statistical difference was found when dynamic deadlift was executed on both surfaces (p>0.05). Conclusion: Isometric deadlift exercise results in significant change in muscle
activity as compared to dynamic deadlift.
Keyword: EMG; BOSU; TrA; Multifidus; Athletes.
Aims and background: To have proper balance, proper communication between body systems and environment is essential. Disruption of these systems causes problems for the individual, which can be seen in diabetic patients with osteoarthritis. Therefore, the aim of this study was to investigate the effect of 8 sessions of balance exercises and traction loops on the joint position sense of the knee and ankle in Diabetic patients had osteoarthritis of the knee. Materials & Methods: This study was performed on elderly diabetic patients with osteoarthritis. Subjects were divided into control and intervention groups and actively and passively reconstructed joint angles and balance time was recorded on both legs. The training phase was balanced. In the test phase, the amount of joint error and balance time on one leg were recorded twice. Correlated t-test was used to compare variables between different pre-training and post-training conditions. The significance level for all analyzes was 0.05. results: The results showed that 45 ° flexion movements of the left knee (P = 0.001), 20 ° flexion of the right knee (P = 0.038), 20 ° flexion of the left knee (P = 0.001), dorsiflexion of the right ankle (P = 0.016) and plantar flexion of the left ankle (P = 0.001) was significantly reduced compared to the pre-exercise stage in the intervention group. Also, no significant difference was observed in the control group. Conclusion: The results of this study showed that trapezoidal loops exercises have improved the reconstruction of joint angles and balance time in diabetic patients with osteoarthritis. Therefore, it is recommended that this type of exercise be included in the exercise program of diabetic patients with elderly osteoarthritis.
The pelvic floor, as a functional muscle, is not only responsible for the function of the lower abdominal organs, but also has a significant influence on posture. Weakened muscles therefore have far-reaching effects. Aside from incontinence syndrome, which noticeably affects quality of life, weak pelvic floor muscles can also cause back pain. There is evidence that many pain syndromes are closely related to fasciae and muscles of the pelvic floor. The drugs used often have many side effects. Preventive measures are therefore highly recommended long before the onset of symptoms, especially since the muscles become weaker with age for physiological reasons. In addition to gymnastics performed under physiotherapeutic guidance, there is also pulse magnetic stimulation (PMS). This form of therapy is far less known, but also works very effectively on the back muscles and body balance. As has been shown in studies, compliance is far higher than with conventional pelvic floor training. Regular training of the pelvic floor muscles is not only an important measure for prevention, but also ensures well-being in terms of core strength. The “pelvic floor” problem affects women and men equally and is therefore also of importance in terms of health policy.
Background and Aim: The core stabilizer muscle weakness can have a negative effect on the balance. On the other hand, the stability of the core area as a connection with the effective transfer of force produced in the lower extremity to the upper limb through the trunk leads to better exercise. Purpose: The present study was carried out to compare the effects of core stability trainings on stable and unstable levels on the female athletes' balance. Materials and Methods: The statistical society of the current study consisted of 30 female athletes from Guilan province who were intentionally selected to take part in the study. They were divided into two groups of 15: stable training and unstable levels of training for 6 weeks, 3 sessions per week. Static balance dynamic balance were evaluated using BESS and Y balance tests, respectively. To analyze the difference in balance between the athletes in the two groups, statistical analysis of covariance and t-correlation analysis were used. Results: The results of the study showed a significant effect of both training protocols on static and dynamic balance (P = 0.001). Also, the results of covariance analysis indicated that training on unstable level had higher efficiency on static and dynamic balance (P <0.05). Conclusion: The results of the present research suggest that, given the difference between the two types of training in affecting the balance component, in addition to the fact that both types of body stabilization trainings can be useful to improve the balance by strengthening the muscles that are Spinal and pelvic controls, coaches and athletes should use unstable levels of core stability training to improve balance.
Bu çalışmanın amacı elit kadın voleybolcuların FHT test skorları ile atletik performans arasındaki ilişkinin belirlenmesidir. Çalışmaya Vestel Venüs Sultanlar Liginde mücadele eden (yaş = 20,6 ± 5,20, boy = 181,4 ±7,81 cm, kg= 69,1 ± 9,02 voleybol yaşı = 9,9 ± 5,6) olan 24 kadın profesyonel voleybolcu gönüllü olarak katılmıştır. Verilerin istatistik analizi için IBM SPSS 23 Statistics programı kullanılmıştır. Verilerin Normallik varsayımı sağlanmadığından ilişkilerin araştırılmasında Spearman korelasyon katsayısı kullanılmıştır. Mevkilere göre testlerin karşılaştırılmasında Kruskal-Wallis testi uygulanmıştır. Çalışma grubuna FHT testini oluşturan, derin çökme (deep squat), engel adımı (hurdle step), ileri düz çökme (in line lunge), omuz hareketliliği (shoulder mobility), aktif düz bacak kaldırma (active straight leg raise), şınav (trunk stability push up), gövde rotasyon dengesi (rotary stability) uygulanmıştır. Atletik performans parametreleri olarak, 20 metre sürat, t çeviklik testi, flamingo denge y dinamik denge testi, dikey sıçrama, otur uzan esneklik, izokinetik bacak ve omuz kuvvetleri değerlendirilmiştir.
Yapılan çalışmanın sonuncunda FHT toplam skor ile atletik performans arasındaki ilişkinin istatistiksel olarak anlamlı olmadığı bulunmuştur (p>0,05). Ancak FHT test bataryasını oluşturan alt testlerden derin çökme hareketi ile sürat performansı arasında negatif yönlü, esneklik ve sıçrama performansları arasında pozitif yönlü (p<0,05) düzeyinde; derin çökme hareketi ile bacak kuvveti arasında ise pozitif yönlü (p<0,01) düzeyinde anlamlı ilişki görülmüştür. Şınav ile izokinetik bacak kuvveti arasında ilişkinin istatistiksel olarak anlamlı pozitif yönde ilişki bulunmuştur (p<0,05). Aktif düz bacak kaldırma ile otur-uzan esneklik testi arasında istatistiksel olarak anlamlı pozitif yönlü ilişki bulunmuştur (p<0,05).
Joint moments are of interest because they bear some relation to muscular effort and hence rider performance. The general objective of this study is to explore the relation between joint moments and pedalling rate (i.e. cadence). Joint moments are computed by modelling the leg-bicycle system as a five-bar linkage constrained to plane motion. Using dynamometer pedal force data and potentiometer crank and pedal position data, system equations are solved on a computer to produce moments at the ankle, knee and hip joints. Cadence and pedal forces are varied inversely to maintain constant power. Results indicate that average joint moments vary considerably with changes in cadence. Both hip and knee joints show an average moment which is minimum near 105 rotations min-1 for cruising cycling. It appears that an optimum rotations min-1 can be determined from a mechanical approach for any given power level and bicycle-rider geometry.
The aim of this study was to determine whether cyclists modify the pattern of force application to become more effective during a prolonged ride to exhaustion. Twelve competitive male cyclists completed a steady-rate exercise ride to exhaustion at 80% of their maximum power output at 90 rev x min(-1) on a cycle ergometer. Pedal force, pedal and crank angle data were collected from an instrumented bicycle for three pedalling cycles at the end of the first and final minutes of the exercise test with simultaneous video recording of the lower limbs. Kinematic and force data were combined to compute hip, knee and ankle joint moments. There were changes in the pattern of force application, joint kinematics and joint moments of force. Comparison of the first minute and the final minute ride revealed significantly increased peak effective force (340 +/- 65.0 and 377 +/- 74.8 N for the first and final minute, respectively; F1,11 = 7.44, P = 0.02), increased positive (28.4 +/- 4.5 and 30.5 +/- 4.8 N x s for the first and final minute, respectively; F1,11 = 7.80, P = 0.02) and negative angular impulses (-1.5 +/- 1.6 and -2.4 +/- 1.5 N x s for the first and final minute, respectively; F1,11 = 4.50, P = 0.06). Contrary to our initial assumptions, it would appear that riders became less effective during the recovery phase, which increased the demand for forces during the propulsive phase. Training the pattern of force application to improve effectiveness may be a useful strategy to prolong an endurance ride.
The aim of this review is to provide greater insight and understanding regarding the scientific nature of cycling. Research findings are presented in a practical manner for their direct application to cycling. The two parts of this review provide information that is useful to athletes, coaches and exercise scientists in the prescription of training regimens, adoption of exercise protocols and creation of research designs. Here for the first time, we present rationale to dispute prevailing myths linked to erroneous concepts and terminology surrounding the sport of cycling. In some studies, a review of the cycling literature revealed incomplete characterisation of athletic performance, lack of appropriate controls and small subject numbers, thereby complicating the understanding of the cycling research. Moreover, a mixture of cycling testing equipment coupled with a multitude of exercise protocols stresses the reliability and validity of the findings. Our scrutiny of the literature revealed key cycling performance-determining variables and their training-induced metabolic responses. The review of training strategies provides guidelines that will assist in the design of aerobic and anaerobic training protocols. Paradoxically, while maximal oxygen uptake (V-O(2max)) is generally not considered a valid indicator of cycling performance when it is coupled with other markers of exercise performance (e.g. blood lactate, power output, metabolic thresholds and efficiency/economy), it is found to gain predictive credibility. The positive facets of lactate metabolism dispel the 'lactic acid myth'. Lactate is shown to lower hydrogen ion concentrations rather than raise them, thereby retarding acidosis. Every aspect of lactate production is shown to be advantageous to cycling performance. To minimise the effects of muscle fatigue, the efficacy of employing a combination of different high cycling cadences is evident. The subconscious fatigue avoidance mechanism 'teleoanticipation' system serves to set the tolerable upper limits of competitive effort in order to assure the athlete completion of the physical challenge. Physiological markers found to be predictive of cycling performance include: (i) power output at the lactate threshold (LT2); (ii) peak power output (W(peak)) indicating a power/weight ratio of > or =5.5 W/kg; (iii) the percentage of type I fibres in the vastus lateralis; (iv) maximal lactate steady-state, representing the highest exercise intensity at which blood lactate concentration remains stable; (v) W(peak) at LT2; and (vi) W(peak) during a maximal cycling test. Furthermore, the unique breathing pattern, characterised by a lack of tachypnoeic shift, found in professional cyclists may enhance the efficiency and metabolic cost of breathing. The training impulse is useful to characterise exercise intensity and load during training and competition. It serves to enable the cyclist or coach to evaluate the effects of training strategies and may well serve to predict the cyclist's performance. Findings indicate that peripheral adaptations in working muscles play a more important role for enhanced submaximal cycling capacity than central adaptations. Clearly, relatively brief but intense sprint training can enhance both glycolytic and oxidative enzyme activity, maximum short-term power output and V-O(2max). To that end, it is suggested to replace approximately 15% of normal training with one of the interval exercise protocols. Tapering, through reduction in duration of training sessions or the frequency of sessions per week while maintaining intensity, is extremely effective for improvement of cycling time-trial performance. Overuse and over-training disabilities common to the competitive cyclist, if untreated, can lead to delayed recovery.
Core stability may provide several benefits to the musculoskeletal system, from maintaining low back health to preventing knee ligament injury. As a result, the acquisition and maintenance of core stability is of great interest to physical therapists, athletic trainers, and musculoskeletal researchers. Core stability is the ability of the lumbopelvic hip complex to prevent buckling and to return to equilibrium after perturbation. Although static elements (bone and soft tissue) contribute to some degree, core stability is predominantly maintained by the dynamic function of muscular elements. There is a clear relationship between trunk muscle activity and lower extremity movement. Current evidence suggests that decreased core stability may predispose to injury and that appropriate training may reduce injury. Core stability can be tested using isometric, isokinetic, and isoinertial methods. Appropriate intervention may result in decreased rates of back and lower extremity injury.
The aim of this study was to analyse the effect of pedalling rate on the pattern of mechanical torque application and on neuromuscular fatigue during prolonged cycling exercise. Eleven well-trained individuals performed three 1-h pedalling sessions, at 50 rev.min-1, 110 rev.min-1 and a freely chosen cadence, at an intensity corresponding to 65% of their maximal aerobic power. The mechanical torque applied on the right pedal was recorded for 30 s every 5 min while pedalling. Contractile and neural properties of the quadriceps and hamstring muscles were analysed before and immediately after each of the three pedalling sessions. The post-exercise reduction in knee extensors maximal voluntary contraction was significant (P<0.01) irrespective of the cadence, but no difference was found between cadences. The use of a particular cadence did not lead to preferentially central or peripheral fatigue. An increase in cadence resulted in greater positive and negative work generated during pedalling. The mechanical pattern was not altered during the exercise, whatever the selected cadence. The present study demonstrates that despite the occurrence of neuromuscular fatigue, trained individuals maintained a stable pedalling pattern throughout an endurance cycling exercise for cadences ranging from 50 to 110 rev.min-1.
The importance of function of the central core of the body for stabilisation and force generation in all sports activities is being increasingly recognised. ‘Core stability’ is seen as being pivotal for efficient biomechanical function to maximise force generation and minimise joint loads in all types of activities ranging from running to throwing. However, there is less clarity about what exactly constitutes ‘the core’, either anatomically or physiologically, and physical evaluation of core function is also variable.
‘Core stability’ is defined as the ability to control the position and motion of the trunk over the pelvis to allow optimum production, transfer and control of force and motion to the terminal segment in integrated athletic activities. Core muscle activity is best understood as the pre-programmed integration of local, single-joint muscles and multi-joint muscles to provide stability and produce motion. This results in proximal stability for distal mobility, a proximal to distal patterning of generation of force, and the creation of interactive moments that move and protect distal joints. Evaluation of the core should be dynamic, and include evaluation of the specific functions (trunk control over the planted leg) and directions of motions (three-planar activity). Rehabilitation should include the restoring of the core itself, but also include the core as the base for extremity function.
Since most previous reports of EMG activation profiles from psoas and the abdominal wall have been qualitative, the objective of this work was to document myoelectric activity from these deep muscles. This knowledge is required to assist in choosing specific training exercises and for making rehabilitation decisions that require knowledge of normalized and calibrated muscle activation levels in different tasks.
Intramuscular EMG was collected from five men and three women, in whom amplitudes were normalized to maximum contraction efforts and reported over a wide variety of clinical and rehabilitation tasks. Electrodes were inserted into vertebral portions of psoas and the three layers of the abdominal wall. Normalized signal amplitudes were reported as peak levels and time histories.
All forms of sit-ups activated psoas (15-35% MVC) more than the curl-up (<10%); psoas was not highly activated during barbell lifting of loads up to 100 kg (< 16% MVC); psoas was most active during maximal hip flexion efforts; push-ups activated psoas up to 25% MVC. Several isometric abdominal exercises were evaluated using the criteria of maximizing abdominal activation while minimizing psoas activity: the side (bridge) support exercise proved the best training method for the abdominal wall.
Consideration of deep muscle activity, provided in this report, is important for choosing the most appropriate rehabilitation and training program for an individual. Specific guidance is provided for choosing the best abdominal exercise, together with activation profiles during lifting, during twisting, and during hip rotation.
The cyclist’s ability to maintain an extremely high rate of energy expenditure for long durations at a high economy of effort is dependent upon such factors as the individual’s anaerobic threshold, muscle fibre type, muscle myoglobin concentration, muscle capillary density and certain anthropometric dimensions. Although laboratory tests have had some success predicting cycling potential, their validity has yet to be established for trained cyclists. Even in analysing the forces producing propulsive torque, cycling effectiveness cannot be based solely on the orientation of applied forces.
Innovations of shoe and pedal design continue to have a positive influence on the biomechanics of pedalling. Although muscle involvement during a complete pedal revolution may be similar, economical pedalling rate appears to differ significantly between the novice and racing cyclist. This difference emanates, perhaps, from long term adaptation.
Air resistance is by far the greatest retarding force affecting cycling. The aerodynamics of the rider and the bicycle and its components are major contributors to cycling economy. Correct body posture and spacing between riders can significantly enhance speed and efficiency.
Acute and chronic responses to cycling and training are complex. To protect the safety and health of the cyclist there must be close monitoring and cooperation between the cyclist, coach, exercise scientist and physician.
Eleven men with recreational bicycling experience rode a bicycle ergometer with instrumented force pedals to determine the effects of pedalling rate and power output on the total resultant pedal force, Fr, and the component of the force perpendicular to the crank arm. The force patterns were obtained at power outputs of 100 W and 200 W for pedalling rates of 40-120 rpm in intervals of 10 rpm. Data were not obtained at 40 rpm at the 200 W power output. The Fr averaged over a crank cycle (Far) was lowest at 90 rpm and 100 W, a value statically different (P less than 0.05) from those at 40, 50, and 120 rpm. At 200 W, the Fr was lowest at 100 rpm, a value statistically different (P less than 0.05) from those at 50, 60, and 70 rpm. The Far varied widely (range of 30% of mean for all subjects) for individuals at a given power output. The results suggest that pedalling at 90-100 rpm may minimize peripheral forces and therefore peripheral muscle fatigue even though this rate may result in higher oxygen uptake.
Overuse problems in cycling can be attributed to several factors. First, the symmetric design of the bicycle matched against the asymmetric variants of the human body produce, on occasion, abnormally directed stress loads on tendons and muscles. Second, cycling involves a high number of repetitions compared with other sports, often as high as 5000 revolutions per hour. Last, with the advent of advanced pedal systems, the cyclist has become more "fixed" to the bicycle. It is critically important that these factors be understood and addressed when treating overuse injuries in cyclists. Standard modalities and therapies are essential components of the treatment plan for cycling-related overuse injuries that should not be overlooked. Surgical intervention should only be considered after prolonged nonoperative measures have failed to relieve symptoms.
Back and neck problems in bicyclists should be managed by a combination of bicycle adjustment or modification, technique change, and medical treatment. The bicycle should be checked for proper fit. Often it is necessary to relieve the rider's extended position by using handlebars with less drop, using a stem with a shorter extension, raising the stem, or moving the seat forward. Changing hand positions on the handlebars frequently, riding with the elbows "unlocked," varying head position, using padded gloves and handlebars, and riding on wider tires all reduce the effects of road shock. Initial medical management includes ice, massage stretching, and nonsteroidal anti-inflammatory drugs or acetaminophen. Definitive treatment is neck and back rehabilitation based on dynamic muscular stabilization. It involves three progressive and overlapping parts: (1) establishing range of motion, (2) finding and stabilizing the neutral position, and (3) adapting the neutral position to exercise.
The influence of a core-strengthening program on low back pain (LBP) occurrence and hip strength differences were studied in NCAA Division I collegiate athletes.
In 1998, 1999, and 2000, hip strength was measured during preparticipation physical examinations and occurrence of LBP was monitored throughout the year. Following the 1999-2000 preparticipation physicals, all athletes began participation in a structured core-strengthening program, which emphasized abdominal, paraspinal, and hip extensor strengthening. Incidence of LBP and the relationship with hip muscle imbalance were compared between consecutive academic years.
After incorporation of core strengthening, there was no statistically significant change in LBP occurrence. Side-to-side extensor strength between athletes participating in both the 1998-1999 and 1999-2000 physicals were no different. After core strengthening, the right hip extensor was, on average, stronger than that of the left hip extensor (P = 0.0001). More specific gender differences were noted after core strengthening. Using logistic regression, female athletes with weaker left hip abductors had a more significant probability of requiring treatment for LBP (P = 0.009)
The impact of core strengthening on collegiate athletes has not been previously examined. These results indicated no significant advantage of core strengthening in reducing LBP occurrence, though this may be more a reflection of the small numbers of subjects who actually required treatment. The core program, however, seems to have had a role in modifying hip extensor strength balance. The association between hip strength and future LBP occurrence, observed only in females, may indicate the need for more gender-specific core programs. The need for a larger scale study to examine the impact of core strengthening in collegiate athletes is demonstrated.
The aim of this pilot study was to examine whether differences existed in spinal kinematics and trunk muscle activity in cyclists with and without non-specific chronic low back pain (NSCLBP). Cyclists are known to be vulnerable to low back pain (LBP) however, the aetiology of this problem has not been adequately researched. Causative factors are thought to be prolonged forward flexion, flexion-relaxation or overactivation of the erector spinae, mechanical creep and generation of high mechanical loads while being in a flexed and rotated position. Nine asymptomatic cyclists and nine cyclists with NSCLBP with a flexion pattern disorder primarily related to cycling were tested. Spinal kinematics were measured by an electromagnetic tracking system and EMG was recorded bilaterally from selected trunk muscles. Data were collected every five minutes until back pain occurred or general discomfort prevented further cycling. Cyclists in the pain group showed a trend towards increased lower lumbar flexion and rotation with an associated loss of co-contraction of the lower lumbar multifidus. This muscle is known to be a key stabiliser of the lumbar spine. The findings suggest altered motor control and kinematics of the lower lumbar spine are associated with the development of LBP in cyclists.
- B L Davis
- And J C O 'connor
VAUGHAN, C.L., B.L. DAVIS, AND J.C. O'CONNOR. Dynamics of Human
Gait. Western Cape, South Africa: Kiboho Publishers, 1991.
Energy expenditure, aerodynamics and medical problems in cycling. An update
FARIA, I.E. Energy expenditure, aerodynamics and medical problems in
cycling. An update. Sports Med. 14:43–63. 1992.