Reproducible Muscle Performance During Constant Work Rate Dynamic Leg Exercise.
Abstract
During constant intensity treadmill or cycle exercise, progressive muscle fatigue is not readily quantified and endurance time is poorly reproducible. However, integration of dynamic knee extension (DKE) exercise with serial measurement of maximal voluntary contraction (MVC) force of knee extensor muscles permits close tracking of leg fatigue. We studied reproducibility of 4 performance indices: MVC force of rested muscle (MVCrest), rate of MVC force fall, time to exhaustion, and percentage of MVCrest (MVCrest) at exhaustion in 11 healthy women (22 + 1 yr) during identical constant work rate 1-leg DICE (1 Hz) on 2 separate days. Means +1- SD, correlation (r) and standard estimate error (S.E.E.) between days were, respectively: a. MVCrest (N), 524 +1-99 vs 517 +1-111,0.91,43.0; b. MVC force fall (N inin-1), -10.77 +1-9.3 vs -11.79 +1-12.1,0.94,3.6; c. Time to exhaustion (min), 22.6+1- 12 vs 23.9+1- 14, 0.98, 2.7; and d. MVCrest at exhaustion, 65 +1-13 vs 62+1- 14, 0.85, 7.8. There were no statistically significant differences between the two test days for any of the performance measures. Low variability of each index should enhance the ability to define the effects of a variety of interventions on voluntary muscle function during constant work rate dynamic leg exercise.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1998
- Accession Number
- ADA347954
Entities
People
- Charles S. Fulco
- Eric Lammi
- Ken W. Kambis
- Paul B. Rock
- Stephen R. Muza
Organizations
- United States Army Research Institute of Environmental Medicine