Article

The acute effects of prior cycling cadence on running performance and kinematics

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Abstract

Purpose: To determine if cycling cadence affects subsequent running speed through changes in stride frequency. Methods: Thirteen male triathletes completed three sessions of testing on separate days. During the first session (control condition), the participants completed a 30-min cycling bout of high intensity at their preferred cadence, immediately followed by a 3200-m run at race effort. During the second and third sessions (fast condition and slow condition), the participants repeated the protocol but with a cycling cadence 20% faster or 20% slower than the control condition. Results: After cycling at a fast cadence, the 3200-m run time averaged nearly a min faster than after cycling at a slow cadence. Running stride frequency after cycling at a fast cadence was significantly greater than after cycling at a normal or slow cadence. Stride length did not differ between conditions. Joint kinematics at foot strike, mid-stance, toe-off, and mid-swing were not different between conditions. Conclusion: Increased cycling cadence immediately before running increased stride frequency and, as a result, increased speed.

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... However, when comparing to triathlon related research it is evident that prior cycling and swimming has an impact on the SR and SL chosen during final run leg (4,12,16,20). Hausswirth et al., (16) reported a decrease in running SL following cycling with no change in SR. Other researchers have concluded that as fatigue increases during running, SR and SL, characteristics begin to alter, with a decrease in SL, and if running velocity is to be maintained an increase in SR (9,16,41). ...
... A limitation of this study to note is that no SR or SL data were collected from the participants in an unfatigued, controlled environment. Previous research has indicated that prior activity such as swimming, cycling or running prior to completing a 10 km run increases fatigue which can alter running mechanics (4,12,16,20). That is, there is a possibility that the participants may choose different SR/SL characteristics while running at a similar speed without prior cycling and or swimming which may have a stronger relationship to the triathletes' body mass or height. ...
... Most of the studies have shown that performance and the stride patterns during running after cycling are greatly influenced by the pedalling frequency during cycling. [87,89,95,182,184] However, the conclusions drawn from such studies are equivocal: Gottschall and Palmer [184] reported that by using a high cadence (FCC +20%) during a 30-minute cycle time trial, the subsequent 3 km running performance was 1 minute faster than by cycling at slow cadence (FCC -20%). This was due to an increased stride frequency whereas stride length was unchanged. ...
... Most of the studies have shown that performance and the stride patterns during running after cycling are greatly influenced by the pedalling frequency during cycling. [87,89,95,182,184] However, the conclusions drawn from such studies are equivocal: Gottschall and Palmer [184] reported that by using a high cadence (FCC +20%) during a 30-minute cycle time trial, the subsequent 3 km running performance was 1 minute faster than by cycling at slow cadence (FCC -20%). This was due to an increased stride frequency whereas stride length was unchanged. ...
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The purpose of this review was to provide a synopsis of the literature concerning the physiological differences between cycling and running. By comparing physiological variables such as maximal oxygen consumption (V O(2max)), anaerobic threshold (AT), heart rate, economy or delta efficiency measured in cycling and running in triathletes, runners or cyclists, this review aims to identify the effects of exercise modality on the underlying mechanisms (ventilatory responses, blood flow, muscle oxidative capacity, peripheral innervation and neuromuscular fatigue) of adaptation. The majority of studies indicate that runners achieve a higher V O(2max) on treadmill whereas cyclists can achieve a V O(2max) value in cycle ergometry similar to that in treadmill running. Hence, V O(2max) is specific to the exercise modality. In addition, the muscles adapt specifically to a given exercise task over a period of time, resulting in an improvement in submaximal physiological variables such as the ventilatory threshold, in some cases without a change in V O(2max). However, this effect is probably larger in cycling than in running. At the same time, skill influencing motor unit recruitment patterns is an important influence on the anaerobic threshold in cycling. Furthermore, it is likely that there is more physiological training transfer from running to cycling than vice versa. In triathletes, there is generally no difference in V O(2max) measured in cycle ergometry and treadmill running. The data concerning the anaerobic threshold in cycling and running in triathletes are conflicting. This is likely to be due to a combination of actual training load and prior training history in each discipline. The mechanisms surrounding the differences in the AT together with V O(2max) in cycling and running are not largely understood but are probably due to the relative adaptation of cardiac output influencing V O(2max) and also the recruitment of muscle mass in combination with the oxidative capacity of this mass influencing the AT. Several other physiological differences between cycling and running are addressed: heart rate is different between the two activities both for maximal and submaximal intensities. The delta efficiency is higher in running. Ventilation is more impaired in cycling than in running. It has also been shown that pedalling cadence affects the metabolic responses during cycling but also during a subsequent running bout. However, the optimal cadence is still debated. Central fatigue and decrease in maximal strength are more important after prolonged exercise in running than in cycling.
... Portanto sugere-se que a seleção da cadência mais elevada no ciclismo melhora o desempenho do atleta na corrida com aumento da frequência de passada, resultando assim, em aumento da velocidade média durante a corrida. 46 Por outro lado, ao comparar o efeito de diferentes cadências (60-100 rpm) de ciclismo no desempenho da corrida nos 3000 m não foram encontradas diferenças entre elas, contudo a escolha de 60 rpm foi associada com uma fração mais elevada de VO 2 máximo sustentada durante a corrida em comparação com as outras condições. Os autores acreditam que há uma maior contribuição do sistema aeróbio em cadências mais baixas, que podem assim, retardar a fadiga por mais tempo na etapa da corrida. ...
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O triatlo caracteriza-se por ser um esporte múltiplo composto por três modalidades: natação, ciclismo e corrida que ocorrem nessa ordem e em sequência. Na etapa da corrida, o atleta sofre efeitos decorrentes das modalidades que a antecederam (natação e ciclismo) podendo assim, alterar parâmetros biomecânicos e fisiológicos da corrida. Objetivo: o objetivo deste estudo foi revisar aspectos fisiológicos, bem como alterações na biomecânica da corrida em triatletas. Método: a busca foi realizada nas bases de dados: Scielo, Pubmed e Google Acadêmico. Resultados: foram incluídos na revisão 48 artigos e um livro. Considerações finais: A corrida de triatletas apresenta alterações na eficiência ventilatória, no VO2 e na cinemática angular, principalmente do joelho e tornozelo. Além disso, triatletas exibem uma maior inclinação do tronco contribuindo para padrões mais econômicos de movimento, especialmente em atletas altamente treinados.
... In cycling there are different rules for different distances, in the case of the Olympic races it is permitted to use the vacuum reducing caloric expenditure and physical exertion [8] significantly improving athlete's running performance [9], already for the longer distances this strategy is not permitted, causing all athletes to start the running in similar conditions of physical wear and tear. The run is the last modality to be performed and researchers report that this running performance should be harmed by muscle stress resulting from the physical exertion of previous tasks [10]. ...
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The aim of the study was to analyze which modality (swimming, cycling or running) may interfere significantly to the final performance of different triathlon events. The present study observed the last five results of Olympic Distance, Half Distance and Full Distance (Ironman) of World Championship from 2010 to 2015. The athlete’s times were tabulated separate per: swimming time, cycling time, running time and total time. The sample was divided in two groups: (G1) athletes who were classified among the five best of each step and (G2) the athletes classified between sixth and tenth place. The total sample was composed by male and female athletes (N=300). Statistical analysis: the regression, correlation and comparison model was used between two groups for the three distances of triathlon tests and for all investigated variables. The results pointed that for each type of test and athlete one modality may be more deterministic to the final performance. Therefore, the training programs should consider that triathlon is one only modality; thus, the training planning should be focused in a unique way taking into account the specificity of race.
... Although there is variety of research on the influence of completing multiple segments on physiological, biomechanical and performance measures ( Bonacci et al., 2010;Bonacci et al., 2013;Cala et al., 2009;Chapman et al., 2008;Gottschall and Plamer, 2002;Hue et al., 1999), to our knowledge there is no research focused specifically on transitions. Even though, transition length (and therefore time) as well as terrain can vary greatly between races, it is important to understand the physiological demands of transitions in order to benefit overall race performance. ...
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Triathletes exiting the swim portion of an event have to decide on how and when to take a wetsuit off (if worn). The purpose of this study was to determine the physiological cost of running while not using a wetsuit, carrying a wetsuit, wearing a wetsuit halfway down or wearing a wetsuit fully up. Participants (n = 20, 30.9 ± 8.7 yrs, 1.71 ± 0.08 m, 71.6 ± 9.5 kg) completed four 5 min running conditions: 1) not wearing the wetsuit, 2) wearing the wetsuit fully up, 3) wearing the wetsuit halfway down, and 4) carrying the wetsuit. A rate of oxygen uptake, a heart rate, ratings of perceived exertion and stride frequency were measured and were each influenced by wetsuit condition (p < 0.05). Each variable (i.e., a rate of oxygen uptake, a heart rate, stride frequency) was lower during running while not wearing the wetsuit vs. any other condition (p < 0.05). The rate of oxygen uptake was greatest during wearing the wetsuit halfway down vs. any other condition (p < 0.05). The heart rate was not different between any of the combinations of either wearing the wetsuit fully up or halfway down or carrying the wetsuit (p > 0.05). The rating of perceived exertion was greater during wearing the wetsuit halfway down vs. carrying the wetsuit (p < 0.05). Stride frequency was lower during not wearing the wetsuit vs. wearing the wetsuit halfway down or fully up (p < 0.05). It was concluded that running with the wetsuit halfway down resulted in the greatest rate of oxygen uptake, heart rate and rating of perceived exertion.
... Since these two tests involve stepping, it is possible that speed-based exercise can facilitate locomotor central pattern generators, which are impaired in this population (Selinov et al, 2013). Others have observed improved gait parameters following a single session speed-dependent treadmill exercise in PD (Pohl et al, 2003) and research on triathletes has shown that a preceding bout of high cadence cycling improves subsequent running speed through an increase in stride frequency (Gottschall and Palmer, 2002), with implications for perseveration (Hudson, 1968). There is an increasing amount of evidence supporting central adaptations following speed-based exercise. ...
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There is growing evidence that speed-based exercise training benefits people with Parkinson's disease (PD). The present study investigates the effects of a single session of volitional, high-speed cycling intervals on a battery of timed functional tests selected for their relevance to the symptom of bradykinesia. Ten subjects with PD (Hoehn-Yahr stage ≤ 3.0) participated in a familiarization session and three test sessions. Functional testing occurred before and after 30 minute sessions in which subjects performed no exercise (NO), pedaled at their preferred cadence (PC), or performed 20, 15-second intervals of high-speed low-resistance cycling (HS-LR). In addition to testing the exercise effects in a within-subjects design, we provide test–retest reliability data, minimal detectable change scores, and correlations among the selected functional tests. Despite the relatively low dose of speed-based exercise, HS-LR elicited significant (p < 0.05) improvements in the four square step test and 10 m walk test. Excepting reaction times, there was high reliability and adequate sensitivity to detect moderate and small differences. Strong correlations among tests of mobility inform the future selection of measures in the experimental design. In addition to what is known about continuous exercise sessions involving high-speed exercise, the present results suggest that brief intervals of HS-LR bicycling are promising and should be examined in a longer duration exercise program.
... In this case, the impact of cycling cadence during a cycle-run combination has received great attention from researchers and coaches. [6,34,[38][39][40] In a simulated triathlon, Hausswirth et al. [34] first demonstrated an indirect effect of cadence upon subsequent running performance. In this study, triathletes selected a cadence of 95 rpm during the drafting condition [reproduced from Pugh, [37] with permission from Blackwell Publishing]. ...
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This review focuses on strategic aspects that may affect performance in a long-duration Olympic event, the Olympic distance triathlon. Given the variety of races during the Olympic Games triathlon, strategic aspects include improving technological features as well as energetics factors affecting overall triathlon performance. During the last decade, many studies have attempted to identify factors reducing the metabolic load associated (or not) with the development of fatigue process by analysing the relationship between metabolic and biomechanical factors with exercise duration. To date, a consensus exists about the benefit of adopting a drafting position during the swimming or the cycling part of the triathlon. Other potential strategic factors, such as the production of power output or the selection of cadence during the cycling or the running leg, are likely to affect the overall triathlon performance. Within this approach, pacing strategies are observed by elite athletes who swim or cycle in a sheltered position, inducing several changes of pace, intensity or stochastic shifts in the amplitude of the physiological responses. The analysis of these parameters appears to arouse some experimental and practical interest from researchers and coachers, especially for long-distance Olympic events.
... Gottschall and Palmer 22 found that a high cadence at the end of the cycling resulted in a high-stride frequency at the beginning of the running part, due to the phenomenon known as perseveration, i.e., persons performing a rhythmic activity for an extended period of time will involuntary continue this movement pattern. 24,25 In the context of multisport events such as triathlons, it is possible that perseveration would cause individuals to unintentionally begin the running bout with a stride frequency similar to the cadence of the previous cycling bout. 23 That could explain the low stride frequencies values and their tendency to decrease obtained in the present study. ...
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Adaptive gaits of humans were produced as a result of emergent properties of a model based on the neurophysiology of the central pattern generator and the biomechanics of the human musculoskeletal system. We previously proposed a neuromusculoskeletal model for human locomotion, in which movements emerged as a stable limit cycle that was generated through the global entrainment among the neural system, composed of neural oscillators, the musculoskeletal system, and the environment. In the present study, we investigated the adaptability of this model under various types of environmental and task constraints. Using a computer simulation, it was found that walking movements were robust against mechanical perturbations, loads with a mass, and uneven terrain. Moreover, the speed of walking could be controlled by a single parameter which tonically drove the neural oscillators, and the step cycle could be entrained by a rhythmic input to the neural oscillators.
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A new principle of sensorimotor control of legged locomotion in an unpredictable environment is proposed on the basis of neurophysiological knowledge and a theory of nonlinear dynamics. Stable and flexible locomotion is realized as a global limit cycle generated by a global entrainment between the rhythmic activities of a nervous system composed of coupled neural oscillators and the rhythmic movements of a musculo-skeletal system including interaction with its environment. Coordinated movements are generated not by slaving to an explicit representation of the precise trajectories of the movement of each part but by dynamic interactions among the nervous system, the musculo-skeletal system and the environment. The performance of a bipedal model based on the above principle was investigated by computer simulation. Walking movements stable to mechanical perturbations and to environmental changes were obtained. Moreover, the model generated not only the walking movement but also the running movement by changing a single parameter nonspecific to the movement. The transitions between the gait patterns occurred with hysteresis.
Article
In this study of human locomotion we investigate to what extent the normal frequency and amplitude of leg movements can be modified voluntarily at different constant velocities, and how these modifications are accomplished in terms of changes in duration and length of the support and swing phases of the stride cycle. Eight healthy male subjects performed walking and running on a motor-driven treadmill at speeds ranging from 1.0 to 3.0 m s-1 (walking) and 1.5 to 8.0 m s-1 (running), respectively. At each speed the subjects walked and ran with: normal stride frequency; the highest possible stride frequency, and the lowest possible stride frequency. Time for foot contact was measured with a special pressure transducer system under the sole of each shoe. At all speeds of walking and running it was possible to either increase or decrease the frequency of leg movements; that is, to decrease or increase stride cycle duration. The range of variation decreased with increasing speed. The mean overall stride frequency range was 0.41 (low frequency walk 1.0 m s-1)-3.57 Hz (high-frequency run 1.5 m s-1). Stride length ranged 0.40 (high frequency walk 1.0 m s-1)-5.00 m (low frequency run 6.0 m s-1). At normal frequency the overall ranges of stride frequency and length were 0.83-1.95 Hz and 1.16-4.10 m, respectively. The stride frequency increased with speed in low frequency walking and running (as in normal frequency) and decreased in high frequency, despite the effort to maintain extreme frequencies. Only in high frequency walking could the stride frequency be kept approximately constant.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
The aim of this study was to investigate the increase in energy cost of running occurring at the end of a triathlon and a marathon event and to link them to the metabolic and hormonal changes, as well as to variations in stride length. Seven subjects took part in 3 experimental situations: a 2 h 15 min triathlon (30 min swimming, 60 min cycling and 45 min running), a 2 h 15 min marathon (MR) were the last 45 min were run at the same speed as the triathlon run (TR), and a 45 min isolated run (IR) done at triathlon speed. The results show that energy cost during MR was higher than during TR (p < 0.01) (+ 8.9%). Similar observations were made for pulmonary ventilation (+ 7.9%) and heart rate (+ 6.3%). Moreover, the values were significantly greater than the values obtained during the IR. TR and MR lead to greater weight loss (p < 0.01) (2.4 +/- 0.3 kg) than IR (1 +/- 0.2 kg). The triathlon and the marathon produced a large decrease in plasma volume (respectively 19.6 +/- 1.4% and 12.9 +/- 1.1%) compared to IR (2 +/- 0.4%). Plasma renin activity was higher for the triathlon and the marathon than for the IR (p < 0.01). MR produces a significantly greater increase in plasma free fatty acids (F.F.A.) than TR (p < 0.05) and IR (p < 0.01). In addition, the F.F.A. at the end of TR were significantly higher than IR (p < 0.05). At the end of the trial the mean stride lengths for TR and IR were greater (+ 15%) (p < 0.01) than for MR. This study, carried out with subjects running overground, confirms the decrease in running efficiency previously shown at the end of a laboratory triathlon, and demonstrates that this decrease is lower than that occurring during a marathon.
Article
The purpose of the present study was to check the increase in energy cost of running at the end of a triathlon and a marathon and to link the decrease in energy cost of running with running kinematic parameters. Seven well-trained triathletes performed 3 experimental trials: a 2 h 15 min triathlon (30 min swimming, 60 min cycling and 45 min treadmill running), a 2 h 15 min marathon where the last 45 min (MR) were run at the same speed as the triathlon run (TR) (i.e. 75% of maximal aerobic speed), and a 45 min isolated run (IR) done at the same speed. Oxygen uptake (VO2), minute ventilation (VE), heart rate (HR), respiratory exchange ratio (RER) and kinematic data were recorded during the 3 exercise runs. The results confirm a higher energy cost during MR compared with TR (+ 3.2%; p <0.05) and IR (+ 11.7%; p <0.01). The triathlon and the marathon were associated with greater weight loss (1.6 +/- 0.02 kg; p <0.01) than the isolated run (0.7 +/- 0.2 kg). After cycling, the mean stride length in TR1 was lower during IR1 and increased at the end of TR. The results show that MR led to decrease in stride length compared with IR. After cycling, the triathletes adopted a more forward leaning posture and the trunk gradient was less marked during the marathon. Moreover, the extension of the knee at foot-strike and the maximal knee angle in non-support phase both increased during MR compared with TR and IR. However, it appears that no single kinematic variable can fully explain the decrease in running efficiency: it seems that running economy during a triathlon and a marathon are linked to global alterations of many different parameters.
Article
We attempted to elicit automatic stepping in healthy humans using appropriate afferent stimulation. It was found that continuous leg muscle vibration produced rhythmic locomotor-like stepping movements of the suspended leg, persisting up to the end of stimulation and sometimes outlasting it by a few cycles. Air-stepping elicited by vibration did not differ from the intentional stepping under the same conditions, and involved movements in hip and knee joints with reciprocal electromyogram (EMG) bursts in corresponding flexor and extensor muscles. The phase shift between evoked hip and knee movements could be positive or negative, corresponding to 'backward' or 'forward' locomotion. Such an essential feature of natural human locomotion as alternating movements of two legs, was also present in vibratory-evoked leg movements under appropriate conditions. It is suggested that vibration evokes locomotor-like movements because vibratory-induced afferent input sets into active state the central structures responsible for stepping generation.