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Influence of Hip Orientation on Wingate Power Output and Cycling Technique
Abstract
The effect of altered hip orientation angle ([HOA] angle of hip joint center to bottom bracket relative to horizontal) on Wingate anaerobic test results and cycling technique while maintaining a constant body configuration angle (included angle between torso, hip, and bottom bracket) and maximum hip-to-pedal distance was examined. Nineteen recreational cyclists, all men, with no recent recumbent cycling experience completed 30-second Wingate tests in 3 recumbent positions (HOA = -20 degrees, -10 degrees, and 0 degrees ) and the standard cycling position (SCP) (HOA = 75 degrees ). Peak, average, and minimum power output, as well as fatigue index, were not significantly different across all positions (p < 0.01). Average hip and knee extension angles increased slightly, and ankle angle did not change as HOA increased. These findings indicate that although HOA does have a small effect on cycling kinematics, these effects are not large enough to alter short-term power output. Therefore, anaerobic power output may be evaluated and compared in the recumbent positions and the SCP.
... Increasing the seat-tube angle increases the inclination of the trunk and therefore improves aerodynamics (Hausswirth et al., 2001). In addition to reducing wind drag the seat forward position may also improve power production by altering muscle forcevelocity and force-length relationships during cycling (Browning et al., 1992;Reiser et al., 2002;Savelberg et al., 2003). It has been proposed that increasing hip joint angle by increasing STA, changes the working length of the muscles crossing the hip, which may change force-producing capabilities of these muscles (Hunter et al., 2003;Savelberg et al., 2003). ...
... Notwithstanding the relevant works published on STA variation during cycling (Garside and Doran, 2000;Heiden and Burnett, 2003;Price and Donne, 1997;Reiser et al., 2002;Ricard et al., 2006), there is still no a common opinion regarding the effects of this bike modification. This lack of conclusive results could be due to the fact that, to the knowledge of the authors, there is not a study concerning this topic that included information of full body kinematic, sEMG and gas exchange data all together. ...
... This result affected the hypothesis that the seat forward position improves power production by altering muscle force-velocity and force-length relationship during cycling (Browning et al., 1992;Reiser et al., 2002;Savelberg et al., 2003). The results obtained with the muscle skeletal model confirmed this aspect showing that the length of muscle tendon complexes was not modified by the position of the seat. ...
One of the most physically demanding parts of triathlon is the transition from cycling to running. Many tri-athletes believe that increasing seat-tube angle (STA) can bring advantages in the following running part. The aim of this study was to evaluate the effects of inverting the support of the seat, for increasing STA, on the metabolic response and on the muscle activation pattern, maintaining a controlled kinematic. Moreover, a muscle-skeletal model was applied to evaluate the hypothesis that increasing STA changes force-producing capabilities of muscles crossing the hip. Ten tri-athletes cycled at two different power levels and with two different STA's. Gas exchange data, kinematics and surface electromyography (sEMG) were acquired during the tests. sEMG was measured from eight muscles of the right side of the body. A model of muscle mechanics and energy expenditure was applied to estimate variations of force production capabilities and muscle energy consumption between the two STA configurations. Inverting the support of the seat showed no significant effects on kinematic, Oxygen consumption, muscle activations and muscle power production capabilities. Nevertheless, an interesting advantage can be the tendency to less activate gastrocnemius and biceps femoris: this could lead to minor muscle fatigue during the following running phase.
... A common concern in these studies was the applicability of a cycle ergometer test for assessing anaerobic power in athletes who primarily perform sprinting activities. Others have studied the eff ects of the standing and the sitting positions [30] , of the The purpose of this work was to apply a simple method for acquisition of power output (PO) during the Wingate Anaerobic Test (WAnT) at a high sampling rate ( S R ) and to compare the eff ect of lower S R on the measurements extracted from the PO. 26 male subjects underwent 2 WAnTs on a cycle ergometer. The reference PO was calculated at 30 Hz as a function of the linear velocity, the moment of inertia and the frictional load. ...
... Others have studied the eff ects of the standing and the sitting positions [30] , of the The purpose of this work was to apply a simple method for acquisition of power output (PO) during the Wingate Anaerobic Test (WAnT) at a high sampling rate ( S R ) and to compare the eff ect of lower S R on the measurements extracted from the PO. 26 male subjects underwent 2 WAnTs on a cycle ergometer. The reference PO was calculated at 30 Hz as a function of the linear velocity, the moment of inertia and the frictional load. The PO was sampled at 0.2, 0.5, 1, 2 and 5 Hz. ...
... Direct inter-study comparison is confounded by the many methodological variants of the WAnT and the analytical limitations inherent in several studies [1] . These factors, as well as the eff ects of inertia [17,33] and of body positioning [29,30] might aff ect the interpretation of cycle ergometer power tests and cause misinterpretation of WAnT results. For instance, the discrete PO values found in this study were achieved by non-athletes, and were comparable to the presented in the literature achieved by athletes [4,12,21] . ...
The purpose of this work was to apply a simple method for acquisition of power output (PO) during the Wingate Anaerobic Test (WAnT) at a high sampling rate ( S(R)) and to compare the effect of lower S(R) on the measurements extracted from the PO. 26 male subjects underwent 2 WAnTs on a cycle ergometer. The reference PO was calculated at 30 Hz as a function of the linear velocity, the moment of inertia and the frictional load. The PO was sampled at 0.2, 0.5, 1, 2 and 5 Hz. Both the peak (16.03±2.22 W·kg (-1)) and mean PO (10.34±1.01 W·kg (-1)) presented lower relative values when the S(R) was lower. Peak PO was attenuated by 0.29-42.07% for decreasing sampling rates, resulting in different values for 0.2 and 1 Hz ( P<0.001). When the S(R) was 0.2 Hz, the time to peak was delayed by 53.81% ( P<0.001) and the fatigue index was attenuated by 22.12% ( P<0.001). In conclusion, due to the differences achieved here and the fact that the peak flywheel frequency is around 2.3 Hz, we strongly recommend that the PO be sampled at 5 Hz instead of 0.2 Hz in order to avoid biased errors and misunderstandings of the WAnT results.
... Three studies to date have compared different positions in the Wingate test. Reiser and colleagues (9) compared a single Wingate test in the seated position against a single Wingate test in the standing position, and they compared different seated positions in another study (10). Reiser et al. (9), who used 8.5% body weight, observed that college cyclists produced greater peak, average, and minimum (5-second periods) power in the standing position. ...
... Peak (5-second periods) power was greater in the seated position. Reiser et al. (10) found that recreational cyclists generated no differences in peak, average, or minimum power outputs when executing a Wingate test in 3 recumbent positions (hip orientations of 220°, 210°, and 0°) to the standard position (hip orientation of 75°). ...
... (WinU1:WinD1); 51.3 , 56.9% (WinU1:WinD1) (7); 50.5 = 52.2% (WinU:WinD) (9); and 54 = 55 = 55 = 55% (220°:210°:0°:75°) (10). As the only difference in power decline by position was found with the physical education subjects (7), the greater resistance does not seem to lead to a lower minimum power relative to the peak power generated in subjects who are at least recreationally trained. ...
Observations of athletes in seated and standing cycling positions in laboratory and field settings have led to the perception that they produce different outputs. The purpose of this study was to determine whether there are differences in power output and physiological responses between seated and standing positions of athletes during 3 consecutive Wingate tests. Seven (n = 7) elite-level speedskaters completed 3 x 30-second Wingate tests (resistance = 7.5% body weight) with 3.5 minutes of recovery between each test in both seated and standing positions. During the recovery period, athletes pedaled against no resistance in the seated position. Testing was randomized and separated by at least 48 hours. Power output, heart rate, blood lactate, and muscle oxygenation data were collected. Statistical analysis of comparable tests (i.e., seated Wingate test 1 [WinD1] compared with standing Wingate test 1 [WinU1]; WinD2:WinU2; WinD3:WinU3) revealed no significant differences between the seated and standing variables. Position during a short-duration maximal-effort exercise test on a stationary bike did not produce statistically different results in power, maximal heart rate, blood lactate, or muscle oxygenation. As no differences were detected between positions, practitioners can allow subjects to choose their position. Also, if a subject rises out of the seat during a "seated" test, this change may not affect the subject's physiological variables. However, transitioning from one position to the other during the test is not advised due to the possible chance of injury. It should be acknowledged that there may be reasons for stipulating one position over another (e.g., injuries, leg length).
... The choice of the position in which the individual cycles is important to consider because the biomechanics and efficiency of cycling in adults have been shown to be affected by seat height, crank arm length, and foot position. [1][2][3][4][5][6][7][8][9][10][11] Cadence (number of revolutions per minute) and workload (resistance or power) also have been shown to be important factors. 1,[7][8][9][10][11][12][13][14][15][16][17][18][19][20] Careful consideration needs to be given to these choices for individuals with disabilities. ...
... Numerous studies have examined the biomechanics of cycling in adult recreational and competitive cyclists who are healthy. In these studies, many biomechanical aspects of adult cycling have been examined, including joint kinematics, [3][4][5][6]10,11,[21][22][23][24][25] kinetics, 1-4,7,9,10,18 -20,23,24,26 -31 muscle activity using electromyography (EMG), 8,22,25,27,29,[31][32][33] energy expenditure, 6,12,13,32,34 -37 and the effects of different workloads, 1,10 -12,14 -16,18,28,30,32 cycling cadences, 1,[7][8][9][12][13][14]17,19,20,22,30 and positioning of the subject on the bicycle. [1][2][3][4][5][6][7][8][9][10][11]27,38 The Table provides an overview of the variables examined in each study. ...
... In these studies, many biomechanical aspects of adult cycling have been examined, including joint kinematics, [3][4][5][6]10,11,[21][22][23][24][25] kinetics, 1-4,7,9,10,18 -20,23,24,26 -31 muscle activity using electromyography (EMG), 8,22,25,27,29,[31][32][33] energy expenditure, 6,12,13,32,34 -37 and the effects of different workloads, 1,10 -12,14 -16,18,28,30,32 cycling cadences, 1,[7][8][9][12][13][14]17,19,20,22,30 and positioning of the subject on the bicycle. [1][2][3][4][5][6][7][8][9][10][11]27,38 The Table provides an overview of the variables examined in each study. These studies provide useful information for physical therapists who use cycling as an intervention. ...
Individuals with physical disabilities may benefit from cycling interventions, which could address impairments while potentially minimizing stress on joints. Improvements in impairments may then have an impact on mobility, activity, and participation. Cycling studies with adults and children who are healthy have shown that many factors can influence the biomechanics of cycling. These factors include seat height, crank arm length, foot position, cadence, and workload. Knowledge of these factors is important for rehabilitation professionals who prescribe cycling as an intervention for individuals with disabilities, because changing these factors can potentially influence the therapeutic outcomes. In addition, further research is needed to fully understand the effect of these factors on individuals with disabilities.
... Preferred seat configuration (i.e., seat height, seat tube angle and pelvic orientation) can vary greatly between individual riders and racing disciplines. A number of studies have investigated the influence of seat configuration on lower limb kinematics and kinetics (e.g., de Groot et al., 1994; and performance metrics such as metabolic cost (e.g., Gnehm et al., 1997;Grappe et al., 1998;Welbergen & Clijsen, 1990), muscle activity (e.g., Silder et al., 2009), and power output (e.g., Reiser et al., 2002;Too, 1991;Umberger et al., 1998) . Both seat height and pelvic orientation have been shown to alter lower extremity kinematics and muscle function during pedaling. ...
... This result was consistent with the findings of Browning et al. (1992) who observed a similar shift in pedal angle as they moved the seat forward when studying pedal forces in elite triathletes and competitive cyclists. Similarly, other studies have shown that variations in STA while fixing the seat height have little effect on the mean and range of knee and ankle angles (e.g., Heil et al., 1997;Reiser et al., 2002;Silder et al., 2009). The generic musculoskeletal model used in this study generated an average maximum crank power of 981.3 W, which is similar to the optimal value of 1000 W reported by Yoshihuku and Herzog (1996) for their pedaling simulations incorporating experimentally determined optimal muscle fiber lengths. ...
Manipulating seat configuration (i.e., seat tube angle, seat height and pelvic orientation) alters the bicycle-rider geometry, which influences lower extremity muscle kinematics and ultimately muscle force and power generation during pedaling. Previous studies have sought to identify the optimal configuration, but isolating the effects of specific variables on rider performance from the confounding effect of rider adaptation makes such studies challenging. Of particular interest is the influence of seat tube angle on rider performance, as seat tube angle varies across riding disciplines (e.g., road racers vs. triathletes). The goals of the current study were to use muscle-actuated forward dynamics simulations of pedaling to 1) identify the overall optimal seat configuration that produces maximum crank power and 2) systematically vary seat tube angle to assess how it influences maximum crank power. The simulations showed that a seat height of 0.76 m (or 102% greater than trochanter height), seat tube angle of 85.1 deg, and pelvic orientation of 20.5 deg placed the major power-producing muscles on more favorable regions of the intrinsic force-length-velocity relationships to generate a maximum average crank power of 981 W. However, seat tube angle had little influence on crank power, with maximal values varying at most by 1% across a wide range of seat tube angles (65 to 110 deg). The similar power values across the wide range of seat tube angles were the result of nearly identical joint kinematics, which occurred using a similar optimal seat height and pelvic orientation while systematically shifting the pedal angle with increasing seat tube angles.
... Several differences between running and cycling can be derived from kinesiological studies. In cycling (19,20), the knee joint is more flexed during the loaded phase than in running (10, 23) (Fig. 1). This indicates that, in cycling, the monoarticular vastus muscles work at longer lengths compared with running. ...
... The net active knee joint moment was calculated by distracting the passive knee joint moment from the maximal gross active knee joint moment. This maximal (10,23) and cycling (19,20). The diagonal lines in this plot represent isolength curve for rectus femoris (RF) muscle (5); from bottom-left to top-right elongation of the muscle occurs. ...
Motor actions are governed by coordinated activation of mono- and biarticular muscles. This study considered differences in mono- and biarticular knee extensors between runners and cyclists in the context of adaptations to task-specific movement requirements. Two hypotheses were tested: 1) the length-at-use hypothesis, which is that muscle adapts to have it operate around optimal length; and 2) the contraction-mode hypothesis, which is that eccentrically active muscles prefer to operate on the ascending limb of the length-force curve. Ten runners and ten cyclists performed maximal, isometric knee extensions on a dynamometer at five knee and four hip joint angles. This approach allowed the separation of the contribution of mono- and biarticular extensors. Three major differences occurred: 1) compared with runners, monoarticular extensors of cyclists reach optimal length at larger muscle length; 2) in runners, optimal length of the biarticular extensor is shifted to larger lengths; and 3) the moment generated by monoarticular extensor was larger in cyclists. Mono- and biarticular extensors respond to different adaptation triggers in runners and cyclists. Monoarticular muscles seem to adapt to the length-at-use, whereas biarticular muscles were found to be sensitive to the contraction-mode hypothesis.
... It was composed of 12 high-resolution cameras of four megapixels operating at a nominal frame rate of 100 Hz. The 3D coordinate data of the markers were smoothed using a second-order Butterworth low-pass filter with a cutoff frequency of 10 Hz (Reiser et al., 2002, Sinclair et al., 2014. ROM was calculated for nine anatomical degrees of freedom (DOF): hip, knee flexion/extension (fle./ext.); ...
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.
... As hip angle increases the length of bi-articulate muscles crossing the hip (Rectus Femoris, Biceps Femoris, Semimembranosus and Semitendinosus) are systematically altered. Researchers have suggested that increasing hip angle enhances power production from these muscles by altering their force-velocity and/or length-tension relationships (19,22). Garside and Doran (4) subsequently demonstrated that steeper STA attenuated fatigue associated with transitioning from cycling to running and improved subsequent 10-km running time. ...
Previous studies have reported improved efficiency at steeper seat tube angle (STA) during ergometer cycling; however, neuromuscular mechanisms have yet to be fully determined. The current study investigated effects of STA on lower limb EMG activity at varying exercise intensities. Cyclists (n=11) were tested at 2 workloads; 160W and an individualised workload (IWL) equivalent to lactate threshold (TLac) minus 10%δ (derived from maximal incremental data), using 3 STA (70, 75 and 80°). Electromyographic data from Vastus Medialis (VM), Rectus Femoris (RF), Vastus Lateralis (VL) and Biceps Femoris (BF) were assessed. The timing and magnitude of activation were quantified and analysed using a two-way ANOVA. STA had significant (P < 0.05) effects on timing of onset and offset of VM, timing of offset of VL, and angle at peak for RF, all occurring later at 80 vs. 70° STA at IWL. In RF, increased activity occurred during the first 108° of the crank cycle at 80 vs. 70° at IWL (P < 0.01). As most of the power in the pedal stroke is generated during the mid-section of the down-stroke, movement of the activation range of knee extensors into the predominantly power phase of the pedal stroke would potentially account for increased efficiency and decreased cardio-respiratory costs. Greater activity of bi-articular RF, in the first 108º of the crank cycle at IWL (80 vs. 70º) may more closely resemble the pelvic stabilising activity of RF in running biomechanics; and potentially explain the more effective transition from cycling to running reported in triathletes using steeper STA.
... As componentes da força aplicada no pedal, assim como a cinemática do membro inferior direito foram sincronizadas por meio de um dispositivo eletrônico. Estas foram filtradas por meio de um filtro digital passa baixa do tipo Butterworth de ordem 3, com freqüência de corte de 10 Hz (Marsh et al., 2000) para as forças e de 4 Hz para as variáveis cinemáticas (Reiser et al., 2002). Os ângulos articulares foram definidos como o representado na figura 1. ...
... Marcadores reflexivos foram posicionados sobre saliências ósseas do membro inferior direito, sendo elas o trocânter maior do fêmur, o côndilo lateral do fêmur e o maléolo lateral, assim como sobre a inclusão de marcadores no eixo de rotação entre o pedal e o pé-de-vela e as extremidades anterior e posterior do pedal(Marsh et al., 2000). As variáveis cinemáticas foram adquiridas durante dez ciclos completos de pedalada.Para análise dos dados cinemáticos foi aplicado um filtro digital passa baixa de ordem 3 do tipo Butterworth com freqüência de corte de 4 Hz sobre os dados cinemáticos(Reiser et al., 2002). Os ângulos articulares foram definidos como representado na figura 2. ...
... The experiments were performed with a "Slyway Hyper" recumbent bicycle (SlyWay®; Slyway Project, Cremona, Italy) and a "Velo Route Tribian 300" upright bicycle (B'Twin®; Decathlon). According to the literature (Reiser, Peterson, & Broker, 2002), the posture of the riders on the bicycles was evaluated in terms of body configuration (BC) angle (123 ± 4°i n NB and 143 ± 1°in RB), hip orientation (HO) angle (75 ± 0°i n NB and 0 ± 1°in RB), and Torso angle (TA) (133 ± 4°in NB and 36 ± 2°in RB) (see Figure 1). ...
Recumbent bicycles (RB) are high performance, human-powered vehicles. In comparison to normal/upright bicycles (NB) the RB may allow individuals to reach higher speeds due to aerodynamic advantages. The purpose of this investigation was to compare the non-aerodynamic factors that may potentially influence the performance of the two bicycles. 3D body centre of mass (BCoM) trajectory, its symmetries, and the components of the total mechanical work necessary to sustain cycling were assessed through 3D kinematics and computer simulations. Data collected at 50, 70, 90 110 rpm during stationary cycling were used to drive musculoskeletal modelling simulation and estimate muscle-tendon length. Results demonstrated that BCoM trajectory, confined in a 15-mm side cube, changed its orientation, maintaining a similar pattern across all cadences in both bicycles. RB displayed a reduced additional mechanical external power (16.1 ± 9.7 W on RB vs. 20.3 ± 8.8 W on NB), a greater symmetry on the progression axis, and no differences in the internal mechanical power compared to NB. Simulated muscle activity revealed small significant differences for only selected muscles. On the RB, quadriceps and gluteus demonstrated greater shortening, while biceps femoris, iliacus, and psoas exhibited greater stretch; however, aerodynamics still remains the principal benefit.
... One major consideration when performing the Wingate test is the manipulation of the test variables, which can result in power outputs based upon unequal scales. There is a wide body of literature that supports the notion that altering any test conditions, from hip and trunk position (17)(18)(19)22) to the type and time of the resistance applied (1,2,5,6,(9)(10)(11)(12)14,27), can dramatically impact the outcome of the anaerobic test. Therefore, the same subject can perform the Wingate test under the different test parameters and produce different power outputs. ...
The purpose of this investigation was to determine potential gender differences in power output at greater flywheel resistances during the Wingate anaerobic cycle test. Twenty-nine competitive cyclists (13 females, 16 males) who met the inclusionary criteria of a VO2 max of at least 3.0 L•min -1), performed on four separate occasions the Wingate test on an electronically braked cycle ergometer. Two trials were performed at each of the randomized flywheel resistances of 0.080 kg/kgbw or 0.095 kg/kgbw, with a minimum of 48 hrs rest between trials. There were no differences in power output between trials at the same resistance, indicating very good test repeatability. Regardless of gender, all power output results were significantly greater with the 0.095 kg/kg bw resistance than the 0.080 kg/kg bw resistance. While the females were able to produce a greater increase in peak power with the heavier resistance (0.095 kg/kg bw), there was also an increased rate of fatigue that indicated the female cyclists were unable to maintain the same intensity as the male cyclists. Finally, power production values from the Wingate anaerobic cycle test are dependent upon the resistance used during the test; the greater the resistance, the greater the power produced.
... Although Too (36) found that varying the subject's trunk angles can yield significantly different power output in the WAnT. Reiser et al. (28) more recently demonstrated that changing hip orientation angle as drastically as a recumbent position vs. traditional cycling position does not affect power outcomes. Therefore, trunk angle was not controlled in the present study. ...
Lunn, WR, Zenoni, MA, Crandall, IH, Dress, AE, and Berglund, ML. Lower Wingate Test power outcomes from "all-out" pretest pedaling cadence compared with moderate cadence. J Strength Cond Res 29(8): 2367-2373, 2015-The aim of the present study was to determine the effect of different pretest pedaling cadences on power outcomes obtained during the Wingate Anaerobic Test (WAnT). Vigorously exercising adult men (n = 14, 24.9 ± 1.2 years) and women (n = 14, 20.4 ± 0.6 years) participated in a randomized crossover study during which they performed the 30-second WAnT on a mechanically braked cycle ergometer (0.075 kg·kg body weight) under 2 conditions. Participants pedaled maximally with an unloaded flywheel during 5 seconds before resistance was applied and the test began (FAST). In another trial, participants maintained a moderate cadence (80 revolutions per minute [rpm]) during 5 seconds before the test began (MOD). All other components of the WAnT were identical. Peak power (PP), mean power (MP), minimum power (MinP), fatigue index (%FAT), and maximum cadence during test were recorded. Comparisons were made using a 2 × 2 factorial repeated-measures analysis of variance. Regardless of gender, the FAST condition resulted in 22.2% lower PP (612.6 ± 33.0 W vs. 788.3 ± 43.5 W), 13.3% lower MP (448.4 ± 22.2 W vs. 517.2 ± 26.4 W), 11.7% lower MinP (280.9 ± 14.8 W vs. 318.3 ± 17.2 W), and 9.0% lower %FAT (53.5 ± 1.3% vs. 58.8 ± 1.5%) than MOD condition (p < 0.01; mean ± SD). Similar outcomes were observed within gender. The authors conclude that practitioners of the WAnT should instruct participants to maintain a moderate pedal cadence (∼80 rpm) during 5 seconds before the test commences to avoid bias from software sampling and peripheral fatigue. Standardizing the pretest pedal cadence will be important to exercise testing professionals who compare data with norms or generate norms for specific populations.
... Few published studies have described joint power generation during volitional recumbent cycling of AB subjects. An early study [20] conducted at high workload (250 W) demonstrated, that similar to upright cycling, power was produced during recumbent cycling by concentric muscle work mainly by the knee (55%) and hip extensors and flexors (25%), in a fairly balanced manner. A recent study [21] that investigated AB subjects performing volitional cycling at low workload (30 W), supported these findings by showing that power was mainly concentric and approximately similarly distributed between the knee (57%) and the hip (43%) extensors and flexors. ...
Background:
The goal of Functional Electrical Stimulation (FES) cycling is to provide the health benefits of exercise to persons with paralysis. To achieve the greatest health advantages, patients should produce the highest possible mechanical power. However, the mechanical power output (PO) produced during FES cycling is very low. Unfavorable biomechanics is one of the important factors reducing PO. The purpose of this study was to investigate the primary joints and muscles responsible for power generation and the role of antagonistic co-contraction in FES cycling.
Methods:
Sixteen subjects with complete spinal cord injury (SCI) pedaled a stationary recumbent FES tricycle at 60 rpm and a workload of 15 W per leg, while pedal forces and crank angle were recorded. The joint muscle moments, power and work were calculated using inverse dynamics equations.
Results:
Two characteristic patterns were found; in 12 subjects most work was generated by the knee extensors in the propulsion phase (83% of total work), while in 4 subjects most work was shared between by the knee extensors (42%) and flexors (44%), respectively during propulsive and recovery phases. Hip extensors produced only low net work (12 & 7%). For both patterns, extra concentric work was necessary to overcome considerable eccentric work (-82 & -96%).
Conclusions:
The primary power sources were the knee extensors of the quadriceps and the knee flexors of the hamstrings. The antagonistic activity was generally low in subjects with SCI because of the weakness of the hamstrings (compared to quadriceps) and the superficial and insufficient hamstring mass activation with FES.
... Although Too (36) found that varying the subject's trunk angles can yield significantly different power output in the WAnT. Reiser et al. (28) more recently demonstrated that changing hip orientation angle as drastically as a recumbent position vs. traditional cycling position does not affect power outcomes. Therefore, trunk angle was not controlled in the present study. ...
The aim of the present study was to determine the effect of different pre-test pedaling cadences on power outcomes obtained during the Wingate Anaerobic Test (WAnT). Vigorously-exercising adult males (n = 14, 24.9 ± 1.2 y) and females (n = 14, 20.4 ± 0.6 y) participated in a randomized, crossover study during which they performed the 30-s WAnT on a mechanically-braked cycle ergometer (0.075 kg/kg body weight) under two conditions. Participants pedaled maximally with an unloaded flywheel during 5 s before resistance was applied and the test began (FAST). In another trial, participants maintained a moderate cadence (80 rpm) during 5 s before test start (MOD). All other components of the WAnT were identical. Peak power (PP), mean power (MP), minimum power (MinP), fatigue index (%FAT) and maximum cadence during test (maxRPM) were recorded. Comparisons were made using a 2x2 factorial RMANOVA. Regardless of gender, the FAST condition resulted in 22.2% lower PP (612.6 ± 33.0 W vs. 788.3 ± 43.5 W), 13.3 % lower MP (448.4 ± 22.2 W vs. 517.2 ± 26.4 W), 11.7% lower MinP (280.9 ± 14.8 W vs. 318.3 ± 17.2 W), and 9.0% lower %FAT (53.5 ± 1.3 % vs. 58.8 ± 1.5 %) than in MOD (p < 0.01; means ± sd). Similar outcomes were observed within gender. The authors conclude that practitioners of the WAnT should instruct participants to maintain a moderate pedal cadence (∼80 rpm) during the 5 s before the test commences to avoid bias from software sampling and peripheral fatigue. Standardizing the pre-test pedal cadence will be important to exercise testing professionals who compare data to norms or generate norms for specific populations.
... Increasing the seat tube angle and utilizing aerobars increases the inclination of the trunk and therefore improves cycling aerodynamics (Hausswirth et al., 2001; Heil, 2002). In addition to reducing wind drag, the seat forward position may also improve power production by altering muscle force-velocity and force-length relationships during cycling (Browning et al., 1992; Reiser et al., 2002; Savelberg et al., 2003). Peak power, during cycling, has been shown to be highly correlated with the time required to complete the cycling performance (Bentley et al., 1998; Tan and Aziz, 2005). ...
The purpose of this study was to compare the effects of bicycle seat tube angles (STA) of (72° and 82°) on power production and EMG of the vastus laeralis (VL), vastus medialis (VM), semimembranous (SM), biceps femoris (BF) during a Wingate test (WAT). Twelve experienced cyclists performed a WAT at each STA. Repeated measures ANOVA was used to identify differences in muscular activation by STA. EMG variables were normalized to isometric maximum voluntary contraction (MVC). Paired t-tests were used to test the effects of STA on: peak power, average power, minimum power and percent power drop. Results indicated BF activation was significantly lower at STA 82° (482.9 ± 166.6 %MVC·s) compared to STA 72° (712.6 ± 265.6 %MVC·s). There were no differences in the power variables between STAs. The primary finding was that increasing the STA from 72° to 82° enabled triathletes' to maintain power production, while significantly reducing the muscular activation of the biceps femoris muscle. Key PointsRoad cyclists claim that bicycle seat tube angles between 72° and 76° are most effective for optimal performance in racing.Triathletes typically use seat tube angles greater than 76°. It is thought that a seat tube angle greater than 76° facilitates a smoother bike to run transition in the triathlon.Increasing the seat tube angle from 72 to 82 enabled triathletes' to maintain power production, while significantly reducing the muscular activation of the biceps femoris muscle.Reduced hamstring muscular activation in the triathlon frame (82 seat tube angle) may serve to reduce hamstring tightness following the bike phase of the triathlon, allowing the runner to use a longer stride length.
... They were encouraged to pedal as hard and fast as possible for next 30 s. During the test, the average power output of every 5-s segment (0–5, 5–10, 10–15, 15–20, 20–25, 25–30 s) was calculated, and peak power output, mean power output over 30 s and fatigue index [(highest 5 s peak power -lowest 5 s peak power)/highest 5 s peak power] were obtained (Armstrong et al. 1983; Reiser et al. 2002). ...
To better understand characteristics of neuromuscular fatigue in supramaximal cycling exercise, this study examined changes in surface electromyography (sEMG) frequency during maximal voluntary isometric contractions (MVC) following a 30-s Wingate anaerobic test (WAnT) using discrete wavelet transform (DWT). The changes in sEMG were also compared between DWT and mean frequency (MNF) obtained by fast Fourier transform (FFT). 17 healthy men performed a WAnT with a 7.5 % of body mass load. Knee extensor MVC torque was measured before and 1, 3, 6, 9, 12 and 15 min following WAnT, and sEMG was recorded from vastus lateralis muscle during the torque measures. sEMG was analysed for (RMS), MNF by FFT and frequency domains of DWT (divided into six domains). MVC torque decreased 21–23 % at 3–15 min, RMS increased 26–34 % at 1–15 min, and MNF decreased 8–10 % from baseline (76.3 ± 3.2 Hz) at 1–3 min post-cycling (P < 0.05). The DWT frequency domains showed that the changes lasted longer than MNF such that the intensity increased at 12 and 15 min for domain 2 (125–250 Hz), all time points for domain 3 (62.5–125 Hz), and 1–6 min for domains 4 (31.2–62.5 Hz) and 5 (15.6–31.2 Hz). The magnitude of increase in the intensity at 1 min post-exercise (45–60 %) was largest for domains 3 and 5 (P < 0.05). A significant correlation was evident only between the magnitude of changes in the domain 5 and MNF (r = −0.56). It is concluded that DWT provides information on neuromuscular fatigue that is not detected by MNF derived from FFT.
... During the incremental test, power output was continually recorded to determine the maximal aerobic power output (Passfield and Doust, 2000). Pedal forces and kinematic data were smoothed by a third-order Butterworth low-pass digital filter with a cutoff frequency of 10 Hz (Marsh et al., 2000) and 4 Hz (Reiser Ii, Peterson, and Broker, 2002), respectively. Because the natural frequency of cycling movement was approximately 1.5 Hz (i.e. for 99 rpm), we have chosen 4 Hz for kinematics filter in agreement with the minimum sampling frequency of 2.4 times the event frequency, as per the Nyquist Theorem (Winter, 2005). ...
Technique changes in cyclists are not well described during exhaustive exercise. Therefore the aim of the present study was to analyze pedaling technique during an incremental cycling test to exhaustion. Eleven cyclists performed an incremental cycling test to exhaustion. Pedal force and joint kinematics were acquired during the last three stages of the test (75%, 90% and 100% of the maximal power output). Inverse dynamics was conducted to calculate the net joint moments at the hip, knee and ankle joints. Knee joint had an increased contribution to the total net joint moments with the increase of workload (5-8% increase, p < 0.01). Total average absolute joint moment and knee joint moment increased during the test (25% and 39%, for p < 0.01, respectively). Increases in plantar flexor moment (32%, p < 0.01), knee (54%, p < 0.01) and hip flexor moments (42%, p = 0.02) were found. Higher dorsiflexion (2%, for p = 0.03) and increased range of motion (19%, for p = 0.02) were observed for the ankle joint. The hip joint had an increased flexion angle (2%, for p < 0.01) and a reduced range of motion (3%, for p = 0.04) with the increase of workload. Differences in joint kinetics and kinematics indicate that pedaling technique was affected by the combined fatigue and workload effects.
... This main focus of this study was PP during a 10-second effort and included specific warm-up routines. Previous Wingate research did not provide a standardized warm-up procedure (3,9,11,12,13,15). ...
Maximal power production is of primary importance for many sporting events. Therefore, using a test that has been shown to be both valid and reliable will allow for accurate baseline testing, measurement of progress, and evaluation of performance. This study examined peak power (PP) during repeated Wingate trials after no warm-up (NWU), a steady state warm-up, and an interval warm-up. In a randomized placebo-controlled study, 11 subjects (38 +/- 8.2 years) performed two 10-second Wingate trials with 4 minutes of recovery between efforts. Warm-up protocols were completed before each Wingate trial and were immediately followed by trial I. Peak power was measured during each trial. Results indicate that PP is not significantly (p > 0.05) different from trial I to trial II for either of the warm-up protocols. The NWU trial II was significantly greater than the NWU trial I (855 +/- 230 W > 814 +/- 222 W, p < 0.05) when analyzed with a paired samples t-test. Peak power appears to be greatest after a general self-selected warm-up, but not after a previously intense bike warm-up. When testing for maximal power output via the Wingate anaerobic test, one should allow for a familiarization trial and should ensure full recovery between this trial and the baseline evaluation.
... Several investigators have used a ''fatigue index'' (2,7,16,27,(31)(32)(33)(34)40,41) to describe changes in power output during maximal cycling trials. Fatigue index has provided insight into many aspects of fatigue; however, it does not account for the influence of pedaling rate on power output (i.e., the power-pedaling rate relationship). ...
Previous investigators have quantified fatigue during short maximal cycling trials ( approximately 30 s) by calculating a fatigue index. Other investigators have reported a curvilinear power-pedaling rate relationship during short fatigue-free maximal cycling trials (<6 s). During maximal trials, pedaling rates may change with fatigue. Quantification of fatigue using fatigue index is therefore complicated by the power-pedaling rate relationship.
The purpose of this study was to quantify fatigue while accounting for the effects of pedaling rate on power.
Power and pedaling rate were recorded during Union Cycliste Internationale sanctioned 200-m time trials by eight male (height = 181.5 +/- 4.3 cm, mass = 87.0 +/- 8.0 kg) world-class sprint cyclists with SRM power meters and fixed-gear track bicycles. Data from the initial portion of maximal acceleration were used to establish maximal power-pedaling rate relationships. Fatigue was quantified three ways: 1) traditional fatigue index, 2) fatigue index modified to account for the power-pedaling rate relationship (net fatigue index), and 3) work deficit, the difference between actual work done and work that might have been accomplished without fatigue.
Fatigue index (55.4% +/- 6.4%) was significantly greater than net fatigue index (41.0% +/- 7.9%, P < 0.001), indicating that the power-pedaling rate relationship accounted for 14.3% +/- 7% of the traditional fatigue index value. Work deficit (23.3% +/- 6%) was significantly less than either measure of fatigue (P < 0.001).
Net fatigue index and work deficit account for the power-pedaling rate relation and therefore more precisely quantify fatigue during variable velocity cycling. These measures can be used to compare fatigue during different fatigue protocols, including world-class sprint cycling competition. Precise quantification of fatigue during elite cycling competition may improve evaluation of training status, gear ratio selection, and fatigue resistance.
... Pedal forces and kinematic data were smoothed by means of a 4th order Butterworth low-pass digital filter with a cutoff frequency of 10 Hz (Marsh et al., 2000) and 4 Hz (Reiser et al., 2002), respectively. Joint angles were defined as presented in the Fig. 1. ...
The aim of the present study was to analyze the net joint moment distribution, joint forces and kinematics during cycling to exhaustion. Right pedal forces and lower limb kinematics of ten cyclists were measured throughout a fatigue cycling test at 100% of PO(MAX). The absolute net joint moments, resultant force and kinematics were calculated for the hip, knee and ankle joint through inverse dynamics. The contribution of each joint to the total net joint moments was computed. Decreased pedaling cadence was observed followed by a decreased ankle moment contribution to the total joint moments in the end of the test. The total absolute joint moment, and the hip and knee moments has also increased with fatigue. Resultant force was increased, while kinematics has changed in the end of the test for hip, knee and ankle joints. Reduced ankle contribution to the total absolute joint moment combined with higher ankle force and changes in kinematics has indicated a different mechanical function for this joint. Kinetics and kinematics changes observed at hip and knee joint was expected due to their function as power sources. Kinematics changes would be explained as an attempt to overcome decreased contractile properties of muscles during fatigue.
Anaerobic energy metabolism and agility are significant determinants of performance within the game actions of team sports such as Indoor Soccer (IS) and American Football (AF) where physical activities labeled as explosive power take place intensively (Beam & Adam, 2011). In the study, the agility skills of male participants of Indoor soccer players (ISP; n10) and American Football players (AFP; n10) have been measured by T-test, Illinois agility test and 505 agility tests and the anaerobic energy metabolism, anaerobic capacity (AC) and anaerobic power (AP) has been measured by Wingate anaerobic power test (WAnT) Monark E894 bicycle ergometer. According to the findings of agility and WAnT measurements, ISP has a significant superiority at AP evaluations although AC averages of two groups are similar (p˂0,05). ISP have better scores than AFP at agility tests T-test 23.7% (p<0,05), Illinois agility test 9.6% (p<0,05), 505 test 8.9% (p>0,05). AFP has 9.2% more BMI averages than ISP. Considering the negative effect of BMI on agility skill, this situation is thought to affect the agility skill of AFP negatively. WAnT measurements have enabled us to evaluate the lower extremity power output of the participants of AFP and ISP. It has been recommended to determine the upper extremity power output in order to understand the differences and the anaerobic energy metabolism between two groups better.
Aim. To investigate the amelioration of initial loading in Wingate anaerobic test. Methods. To modify the traditional test on the Monark 834E bicycles, a new testing way (TestW2), loading up before riding to highest velocity, was designed to replace the traditional way (TestW1), loading up after unloaded riding to highest velocity. A comparative study was made among 91 young athletes (57 males and 34 females, aged 12-17) before and after 24 h. Results. Maximal power and average power increased significantly, but descent velocity decreased in TestW2 (t = 0.580 - 0.930, P < 0.01). There was a highly positive correlation between TestW1 and TestW2 (r = 0.83 - 0.96). The initial accelerate index accorded with the demand of speed event-group. Conclusion. TestW2 is more suited to the approximation principle than TestW1. TestW2 helps testees to play their maximal anaerobic ability and output power of motor muscles, and improve the test reliability for functional evaluation of speed event-group.
The study was designed to determine the effect of upright-posture (UP) versus semirecumbent (SR) cycling on commonly used measures of maximal and submaximal exercise capacity. Nine healthy, untrained men (M age = 27 years, SD = 4.8 years) underwent steady-state submaximal aerobic testing followed by a ramped test to determine maximal oxygen consumption (VO2max). Anaerobic peak and average power and total work were assessed with the Wingate test. All tests were performed in both SR and UP positions, in random order. Oxygen consumption (VO2) and ventilation (VE) at the maximum workrate were lower in the SR position (p < .05). At submaximal workrates (50 W and 100 W), VO2 and VE were equivalent in the UP and SR positions, despite differences in tidal volume and respiratory rate (p < .05). There was no difference in peak or average anaerobic power in the two positions. In summary, SR exercise was associated with a reduced VO2max and a significantly altered ventilatory response to aerobic exercise, with no change in anaerobic power output.
The aim of this study was to evaluate changes in the three dimensional lower limb kinematics during a simulated cycling time trial.
Repeated measures.
Ten experienced male road cyclists performed a 60 min cycling test at a workload based on previous onset of blood lactate accumulation (OBLA) testing. The time trial (TT) was divided into six 10 min periods consisting of 8 min cycling at steady state (88% of OBLA) followed by a 90 s effort phase (140% of OBLA) and a 30 s recovery phase (60% of OBLA). Three-dimensional kinematic data (200 Hz) were recorded in the last minute of each steady state phase with specific attention directed at changes in range of motion (ROM) and consistency of orientation at the hip, knee and ankle joints during drive phase.
from repeated measures ANOVA indicated a mean effect for test duration on the drive phase ROM in both hip extension (p=0.027) and ankle dorsi flexion (p<0.001). The SD of the mean tibial rotation during the drive phase was the only measure of movement consistency that showed an effect for test duration (p=0.031).
These findings indicated that participants tended to increase the ROM in hip extension and ankle flexion during drive phase at the end of a TT. Changes in the consistency of tibial rotation during the drive phase may be an important indicator of fatigue and should be monitored by coaches during training due to its possible relationship with injury and fatigue.
The principle of specificity would indicate that being aerobically trained would not necessarily enhance performance in events relying principally on oxygen-independent metabolic pathways (i.e. “anaerobic” exercise). Body fatness may be associated with aerobic and anaerobic performance. VO2 Peak was determined with a graded cycle ergometry and, in a separate session 4 consecutive Wingate power tests (3 min recovery) in 31 males. Pearson correlations were calculated for VO2 Peak and Body Fat Percentage with Peak Power, Mean Power, Minimum Power, Fatigue Index, Peak Heart Rate, and Recovery Heart Rate. No significant correlations were found for VO2 Peak or Body Fat Percentage with Peak Power on any bout (p>0.05). Significant correlations were found for VO2 Peak and Body Fat Percentage with Mean Power, Minimum Power, and Fatigue Index. Significant correlations were found for VO2 Peak with delta values of power performance and heart rates (peak and 3 min recovery). Results indicate that VO2 Peak is associated with repeated anaerobic performance, possibly due to greater capacity to recover between bouts. Body Fat Percentage was correlated with measures of power performance (strongest relationships existing in the earlier bouts), but is not strongly correlated with either the heart rate response to power performance or the change in performance over successive bouts.
Standing during cycling may increase overall muscular activity. However, effects of standing vs. seated posture on performance measures during repeated bouts have not been extensively explored. The purpose of this study was to examine the effects of standing vs. seated posture on repeated Wingate performance. Healthy volunteers (n = 35) performed 3 consecutive Wingate anaerobic power tests (W(1), W(2), W(3)) in a standing (STA) as well as seated (SIT) posture. Within-group comparisons were made for peak power, mean power, minimum power, and fatigue index. Results were considered significant at p < or = 0.05. No significant differences were found for peak power in W(1), W(2), or W(3). No significant difference was found for mean power in W(1) or W(2), but significant differences were found for mean power in W(3) (STA: 451.5 +/- 105.3, SIT: 425.7 +/- 110.0); minimum power in W(1) (STA: 433.6 +/- 100.8, SIT: 381.5 +/- 96.9), W(2) (STA: 348.1 +/- 112.9, SIT: 308.0 +/- 95.8), W(3) (STA: 292.0 +/- 103.6, SIT: 265.3 +/- 90.8); and fatigue index: W(1) (STA: 51.3 +/- 10.7, SIT: 56.9 +/- 9.3), W(2) (STA: 56.5 +/- 12.6, SIT: 61.8 +/- 12.2), W(3) (STA: 59.4 +/- 13.1, SIT: 63.6 +/- 12.4). Results suggest that a standing posture enhances performance during repeated Wingate cycling. The enhancement is most likely due to an attenuated loss in power, which in turn improves fatigue index.
This study investigated the effects of changing cadence and workload on pedaling technique. Eight cyclists were evaluated during an incremental maximal cycling and two 30-minute submaximal trials at 60% and 80% of maximal power output (W(60%) and W(80%), respectively). During submaximal 30-minute trials, they cycled for 10 minutes at a freely chosen cadence (FCC), 10 minutes at a cadence 20% above FCC (FCC+20%), and 10 minutes at a cadence 20% below FCC (FCC-20%). Pedal forces and kinematics were evaluated. The resultant force (RF), effective force (EF), index of effectiveness (IE) and IE during propulsive and recovery phase (IEprop and IErec, respectively) were computed. For W(60%), FCC-20% and FCC presented higher EFmean (69+/-9 N and 66+/-14 N, respectively) than FCC+20% (52+/-14 N). FCC presented the highest IEprop (81+/-4%) among the cadences (74+/-4 and 78+/-5% for FCC-20% and FCC+20%, respectively). For W(80%), FCC presented higher EFmean (81+/-5 N) than FCC+20% (72 +/- 10 N). The FCC-20% presented the lower IEprop (71+/-7%) among the cadences. The EFmin was higher for W(80%) than W(60%) for all cadences. The IE was higher at W (80%) (61+/-5%) than W (60%) (54+/-9%) for FCC+20% (all p<0.05). Lower cadences were more effective during the recovery phase for both intensities and FCC was the best technique during the propulsive phase.
An ergometer for human subjects is described that can be used for leg cycling exercise at low to very high intensities involving concentric or eccentric muscle contractions. Dependent on the mode of exercise (concentric or eccentric) and rpm chosen, 1,500 W constitute the approximate upper limit of power reception or production, and such an intensity far exceeds human capabilities even for very short-term bouts of exercise. The ergometer permits the study of full ranges of exercise intensities for both types of exercise that, for the concentric condition, includes a high component of anaerobic energy release.
While the recumbent cycling position has become common for high-performance human-powered vehicles, questions still remain as to the influence of familiarity on recumbent cycling, the optimal riding position and how recumbent cycling positions compare to the standard cycling position (SCP). Eight recumbent-familiar cyclists and 10 recreational control cyclists were compared using the 30-s Wingate test in 5 recumbent positions as well as the SCP. For the recumbent positions, hip position was maintained 15° below the bottom bracket while the backrest was altered to investigate body configuration angle (BCA: the angle between the bottom bracket, hip, and a marker at mid-torso) changes from 100° to 140° in 10° increments. Between-groups analysis found that only 4 of the 126 analyzed parameters differed significantly, with all trends in the same direction. Therefore both groups were combined for further analysis. Whole-group peak power (14.6 W/kg body mass) and average power (9.9 and 9.8 W/kg body mass, respectively) were greatest in the 130° and 140° BCA positions, with power dropping off as BCA decreased through 100° (peak = 12.4 W/kg body mass; avg. = 9.0 W/kg body mass). Power output in the SCP (peak = 14.6 W/kg body mass; avg. = 9.7 W/kg body mass) was similar to that produced in the 130° and 140° recumbent BCA. Average hip and ankle angles increased (became more extended/plantar-flexed), 36° and 10°, respectively, with recumbent BCA, while knee angles remained constant. The lower extremity kinematics of the 130° and 140° BCA were most similar to those of the SCP. However, SCP hip and knee joints were slightly extended and the ankle joint was slightly plantar-flexed compared to these two recumbent positions, even though the BCA of the SCP was not significantly different. These findings suggest: (a) the amount of recumbent familiarity in this study did not produce changes in power output or kinematics; (b) BCA is a major determinant of power output; and (c) recumbent-position anaerobic power output matches that of the SCP when BCA is maintained, even though lower extremity kinematics may be altered.
The Wingate anaerobic power output test was developed to assess the power output of the muscles called on during a short, maximal anaerobic cycling bout of 30-second duration. This test has traditionally been administered using an upright mechanical cycle ergometer. No known evidence exists in the available literature that the Wingate test has been reliably administered using a recumbent ergometer, an exercise modality experiencing increased popularity for both conditioning and rehabilitation, particularly in aging and disabled populations. This study was designed to compare test-retest measures of peak power output (PPO), mean power output (MPO), and fatigue rate (FR) on electrically braked upright and recumbent cycle ergometers preprogrammed for the 30-second Wingate test protocol. Twenty-three college-aged men (n = 9) and women (n = 14) volunteered for the study. Each subject performed 2 trials on the upright ergometer and 2 trials on the recumbent ergometer with at least 1 day of rest between trials. Trials were randomized over a 2-week period. Resistance was set at 0.075 kg per kilogram of body weight. No significant differences were found between the upright or recumbent ergometers for all 3 variables in men (p > 0.05). Significant intraclass correlations were found between the mean of the upright and recumbent trials for PPO (r = 0.96), MPO (r = 0.99), and FR (r = 0.68). Significant differences were found between upright and recumbent ergometers for PPO and FR, but not in MPO for women (p > 0.05). Significant intraclass correlations were found between the mean of the upright and recumbent trials for PPO (r = 0.98), MPO (r = 0.97), and FR (r = 0.81). The results of this study support the recumbent ergometer as a valid and reliable instrument for measuring PPO, MPO, and FR in men, when compared with an upright cycle ergometer using the Wingate test.
Gravity is a contributing force that is believed to influence strongly the control of limb movements since it affects sensory input and also contributes to task mechanics. By altering the relative contribution of gravitational force to the overall forces used to control pedaling at different body orientations, we tested the hypothesis that joint torque and muscle activation patterns would be modified to generate steady-state pedaling at altered body orientations. Eleven healthy subjects pedaled a modified ergometer at different body orientations (from horizontal to vertical), maintaining the same workload (80 J), cadence (60 rpm), and hip and knee kinematics. Pedal reaction forces and crank and pedal kinematics were measured and used to calculate joint torques and angles. EMG was recorded from four muscles (tibialis anterior, triceps surae, rectus femoris, biceps femoris). Measures of muscle activation (joint torque and EMG activity) showed strong dependence on body orientation, indicating that muscle activity is not fixed and is modified in response to altered body orientation. Simulations confirmed that, while joint torque changes were not necessary to pedal at different body orientations, observed changes were necessary to maintain consistent crank angular velocity profiles. Dependence of muscle activity on body orientation may be due to neural integration of sensory information with an internal model that includes characteristics of the endpoint, to produce consistent pedaling trajectories. Thus, both sensory consequences and mechanical aspects of gravitational forces are important determinants of locomotor tasks such as pedaling.
The standard procedure for determining subject power output from a 30-s Wingate test on a mechanically braked (friction-loaded) ergometer includes only the braking resistance and flywheel velocity in the computations. However, the inertial effects associated with accelerating and decelerating the crank and flywheel also require energy and, therefore, represent a component of the subject's power output. The present study was designed to determine the effects of drive-system inertia on power output calculations.
Twenty-eight male recreational cyclists completed Wingate tests on a Monark 324E mechanically braked ergometer (resistance: 8.5% body mass (BM), starting cadence: 60 rpm). Power outputs were then compared using both standard (without inertial contribution) and corrected methods (with inertial contribution) of calculating power output.
Relative 5-s peak power and 30-s average power for the corrected method (14.8 +/- 1.2 W x kg(-1) BM; 9.9 +/- 0.7 W x kg(-1) BM) were 20.3% and 3.1% greater than that of the standard method (12.3 +/- 0.7 W x kg(-1) BM; 9.6 +/- 0.7 W x kg(-1) BM), respectively. Relative 5-s minimum power for the corrected method (6.8 +/- 0.7 W x kg(-1) BM) was 6.8% less than that of the standard method (7.3 +/- 0.8 W x kg(-1) BM). The combined differences in the peak power and minimum power produced a fatigue index for the corrected method (54 +/- 5%) that was 31.7% greater than that of the standard method (41 +/- 6%). All parameter differences were significant (P < 0.01). The inertial contribution to power output was dominated by the flywheel; however, the contribution from the crank was evident.
These results indicate that the inertial components of the ergometer drive system influence the power output characteristics, requiring care when computing, interpreting, and comparing Wingate results, particularly among different ergometer designs and test protocols.
The Wingate Anaerobic Test
- O Inbar
- O Bar-Or
- J S Skinner
INBAR, O., O. BAR-OR, AND J.S. SKINNER. The Wingate Anaerobic
Test. Champaign, IL: Human Kinetics, 1996.