Pedaling time variability is increased in dropped riding position

Abstract

Variability of cycle-to-cycle duration during a pedaling task is probably related to the rhythmic control of the lower limb muscles as in gait. Although walking variability has been extensively studied for its clinical and physiological implications, pedaling variability has received little attention. The present contribution determines the variability of the cycling time during a 10-min exercise as a function of upper body position. Nine healthy males were required to pedal on cycle-ergometer at a self-selected speed for 10 min in two different upper body positions [hands on upper handlebars (UP) or lower handlebars (DP)]. Time domain measures of cycling variability [total standard deviation (SDtot), mean standard deviation cycle-to-cycle intervals over 100 cycles (SD100), standard deviation of the average cycle-to-cycle intervals over 100 cycles (SDA100)] were measured. Moreover, the same time domain measures were also calculated for heart rate in order to discriminate possible involvements of autonomic regulation. Finally, the structure of the cycle variations has been analyzed in the framework of deterministic chaos calculating the maximum Lyapunov exponents. Significant increases in cycle-to-cycle variability were found for SDtot, SD100 in DP compared to UP, whereas cardiac parameters and other cycling parameters were not changed in the two positions. Moreover, the maximum Lyapunov exponent was significantly more negative in DP. The results suggest that small perturbations of upper body position can influence the control of cycling rhythmicity by increasing the variability in a dissipative deterministic regimen.

Optimisation of starting conditions in track cycling

“…Moreover, preliminary data from a pilot study done with the SRM (Schoberer Rad Messtechnik, Welldorf, Germany) power monitoring system suggested that the maximal power output in Watts (calculated from the torque and angular speed of the crank) was at the crank angle of 71°, independently from the angular speed used (data not shown). Therefore, we also tested the effect of two different initial crank angles: 47°a nd 71°; this setting [38] was calibrated for each start with goniometer (Nokia C6, Finland; error 0.1°). Subjects repeated the test in the same condition four times.…”

The Brain and Movement: How Physical Activity Affects the Brain

“…Th ese works start from the improvement of heart and lung effi cacy to the enhancement of joint function (Padulo, Di Capua & Viggiano, 2012;Padulo et al, 2013;Oliva, Osti, Padulo & Maff ulli, 2014;Gheller et al, 2015); from regulating blood sugar and fat to that of the sleep-wake cycle (Matinez-Gomez et al, 2010;Umpierre et al, 2011;Lang et al, 2013). Obviously, among all the organs of our body, the brain is richly benefi tted by movement, both structurally and functionally.…”

Electromyographic analysis of riding posture during the bicycling start moment

“…The participant's hand position was similar to the stationary cycling task (bottom of the handle bar) and the gear selected was consistent with the stationary cycling task 19 . The same bicycle was used to test all participants.…”

“…However, to verify the effect of the two riding postures on instantaneous cycling speed in a real cycling environment, participants were also required to perform a similar experimental protocol on a race bicycle on a sport-specific oval track. This protocol has been used previously to assess cycling performance 19 .…”

“…1B) as previously described [19][20][21][22] . The linear encoder had a spatial resolution of 0.1 mm (range 3.5 m, max speed 24 m/s) and a sampling frequency of 100 Hz.…”