We used functional magnetic resonance imaging (fMRI) to record human brain activity during slow (30 RPM), fast (60 RPM), passive (30 RPM), and variable rate pedaling. Ten healthy adults participated. After identifying regions of interest, the intensity and volume of brain activation in each region was calculated and compared across conditions (p < .05). Results showed that the primary sensory and motor cortices (S1, M1), supplementary motor area (SMA), and cerebellum (Cb) were active during pedaling. The intensity of activity in these areas increased with increasing pedaling rate and complexity. The Cb was the only brain region that showed significantly lower activity during passive as compared with active pedaling. We conclude that M1, S1, SMA, and Cb have a role in modifying continuous, bilateral, multijoint lower extremity movements. Much of this brain activity may be driven by sensory signals from the moving limbs.
Jay P. Mehta, Matthew D. Verber, Jon A. Wieser, Brian D. Schmit and Sheila M. Schindler-Ivens
Mark Holten Mora-Jensen, Pascal Madeleine and Ernst Albin Hansen
The present study analyzed (a) whether a recently reported phenomenon of repeated bout rate enhancement in finger tapping (i.e., a cumulating increase in freely chosen finger tapping frequency following submaximal muscle activation in the form of externally unloaded voluntary tapping) could be replicated and (b) the hypotheses that the faster tapping was accompanied by changed vertical displacement of the fingertip and changed peak force during tapping. Right-handed, healthy, and recreationally active individuals (n = 24) performed two 3-min index finger tapping bouts at freely chosen tapping frequency, separated by 10-min rest. The recently reported phenomenon of repeated bout rate enhancement was replicated. The faster tapping (8.8 ± 18.7 taps/min, corresponding to 6.0 ± 11.0%, p = .033) was accompanied by reduced vertical displacement (1.6 ± 2.9 mm, corresponding to 6.3 ± 14.9%, p = .012) of the fingertip. Concurrently, peak force was unchanged. The present study points at separate control mechanisms governing kinematics and kinetics during finger tapping.
Elizabeth L. Stegemöller, Joshua R. Tatz, Alison Warnecke, Paul Hibbing, Brandon Bates and Andrew Zaman
incorporated into the treatment of persons with PD. How music style and rate modulate performance in persons with PD, though, have been neglected and remain limited in healthy young populations. Thus, the primary purpose of this study was to determine how differing styles of music and movement rate influence
Winston D. Byblow, Jeffery J. Summers, Andras Semjen, Irina J. Wuyts and Richard G. Carson
Two experiments required right-handed subjects to trace circular trajectories while complying with either a symmetric or asymmetric pattern. In symmetric patterns, circles were traced in a mirror image either inward or outward. In asymmetric patterns, circles were traced in the same direction either clockwise or counterclockwise. Subjects were instructed to trace with spatial accuracy while maintaining a strict temporal relationship to a metronome that scaled movement rates from 1.25 to 3 Hz. The symmetric patterns were more stable than asymmetric patterns; the circularity of trajectories was greater for the dominant side; and there were spontaneous reversals in the direction of circling in the nondominant limb when performing asymmetric patterns. The second experiment examined the same subjects under the instruction of intentionally changing the pattern by reversing the left or right limb circling direction when cued to do so. The degree of interlimb interference was highly asymmetric and contingent on the direction of pattern change. Intentional direction reversals were more expedient and with less disruption to the contralateral limb when asymmetric to symmetric pattern changes were effected through a reversal in the direction of nondominant side. The results are interpreted with reference to evidence that the supplementary motor area mediates descending input to the upper limbs during disparate bimanual actions, but not during symmetric actions.
Philip Davis, Peter R. Benson, Robert Waldock and Andrew J. Connorton
Female boxing debuted at the 2012 London Olympic Games. To better understand the performance aspects of the sport, video footage of eighteen 4 × 2-min bouts were analyzed. The boxers involved in the competition were of an elite level (mean ± SD), age 26.4 ± 4.6 y, height 169.3 ± 6.2 cm, and weight 60.3 ± 10.0 kg. Analysis revealed an activity rate of ~1.6 actions/s, including ~16 punches, ~3.3 defensive movements, and ~63 vertical hip movements, all per minute, over the 4 × ~132-s rounds (R). A 2 × 4 (outcome × round) ANOVA with repeated measures over the rounds was used to analyze the data. Winners maintained a higher activity rate in round 1 (R1) and R2; a higher movement rate in R2, R3, and R4; and an increased punch accuracy including the ratio of total punches to punches landed in R3 and air punches as a percentage of punches missed in R1 and R3. Specific techniques that discriminate between successful and unsuccessful female amateur boxers include the straight rear-hand and body punches, higher for winners in R1, as well as uppercut punches and defensive foot movements, higher for winners in R4. Findings highlight the current demands of elite amateur female boxing. These data will be useful for those designing training programs and may also be useful for guiding sport-specific fitness testing.
Darren Burgess, Geraldine Naughton and Kevin Norton
The understanding of the gap between Under 18 y (U18) and senior-level competition and the evolution of this gap in Australian Football lack a strong evidence base. Despite the multimillion dollars invested in recruitment, scientific research on successful transition is limited. No studies have compared individual players’ movement rate, game statistics and ball speed in U18 and senior competition of the Australian Football League across time. This project compared differences in player movement and ball speed between matches from senior AFL competitive matches and U18 players in the 2003 and 2009 seasons.
TrakPerformance Software and Global Positioning System (GPS) technology were used to analyze the movement of players, ball speed and game statistics. ANOVA compared the two levels of competition over time.
Observed interactions for distance traveled per minute of play (P = .009), number of sprints per minute of play (P < .001), time spent at sprint speed in the game (P < .001), time on field (P < .001), and ball speed (P < .001) were found. Subsequent analysis identified increases in movement patterns in senior AFL competition in 2009 compared with the same level of competition in 2003 and U18 players in 2003 and 2009.
Senior AFL players in 2009 were moving further, sprinting relatively more frequently, playing less time and playing at game speeds significantly greater than the same senior competition in 2003 as well as compared with both cohorts of U18 players.
Kara N. Gange, Michael C. Kjellerson and Christiane J. Berdan
ultrasound treatment began once the intramuscular temperature had remained stable for 1 minute and was set at the following parameters: 3 MHz frequency, 1.0 W/cm 2 intensity, and 20 minutes treatment time. To ensure the transducer movement rate was consistently at 4 centimeters per second, a metronome was
Brice T. Cleland and Sheila Schindler-Ivens
.P. , Verber , M.D. , Wieser , J.A. , Schmit , B.D. , & Schindler-Ivens , S.M. ( 2012 ). The effect of movement rate and complexity on functional magnetic resonance signal change during pedaling . Motor Control , 16 ( 2 ), 158 – 175 . PubMed doi:10.1123/mcj.16.2.158 22357094 10.1123/mcj.16
bowlers with 100% accuracy, thereby adding to its generalisability, and both theoretical and applied value. Funding source: The England & Wales Cricket Board (ECB). Leg movement rate pre- and post-kicking intervention in infants with Down syndrome Rahil Khasgiwale, University of Southern California; Beth