| Title | Effect of body tilt angle on fatigue and EMG activities in lower limbs during cycling. | | Author(s) | Egaña M, Ryan K, Warmington SA, Green S | | Institution | Department of Physiology, Trinity College Dublin, Dublin, Ireland, megana@tcd.ie. | | Source | Eur J Appl Physiol 2009 Nov 5. | | Abstract | This study compared the rate of fatigue and lower limb EMG activities during high-intensity constant-load cycling in upright and supine postures. Eleven active males performed seven cycling exercise tests: one upright graded test, four fatigue tests (two upright, two supine) and two EMG tests (one upright, one supine). During the fatigue tests participants initially performed a 10 s all-out effort followed by a constant-load test with 10 s all-out bouts interspersed every minute. The load for the initial two fatigue tests was 80% of the peak power (PP) achieved during the graded test and these continued until failure. The remaining two fatigue tests were performed at 20% PP and were limited to the times achieved during the 80% PP tests. During the EMG tests subjects performed a 10 s all-out effort followed by a constant-load test to failure at 80% PP. Normalised EMG activities (% maximum, NEMG) were assessed in five lower limb muscles. Maximum power and maximum EMG activity prior to each fatigue and EMG test were unaffected by posture. The rate of fatigue at 80% PP was significantly higher during supine compared with upright posture (-68 +/- 14 vs. -26 +/- 6 W min(-1), respectively, P < 0.05) and the divergence of the fatigue responses occurred by the second minute of exercise. NEMG responses were significantly higher in the supine posture by 1-4 min of exercise. Results show that fatigue is significantly greater during supine compared with upright high-intensity cycling and this effect is accompanied by a reduced activation of musculature that is active during cycling. | | Language | ENG | | Pub Type(s) | JOURNAL ARTICLE
| | PubMed ID | 19890660 |
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