Assessment of the two-point method applied in field conditions for routine testing of muscle mechanical capacities in a leg cycle ergometer

Abstract

The aim of this study was to compare the reliability and magnitude of the force-velocity (F-V) relationship parameters [maximum force (F0), maximum velocity (V0), F-V slope, and maximum power (P0)] obtained through the application of only two loads (i.e., two-point method) vs. six loads (i.e., multiple-point method). Ten physically active men (age 19.5 ± 0.9years, body mass 79.0 ± 9.0kg, height 183.9 ± 8.4cm) conducted four testing sessions after a preliminary familiarization session with the leg cycle ergometer exercise. In a counterbalanced order, subjects performed two sessions of the multiple-point method (six loads applied for the F-V modeling) over 1week and two sessions of the two-point method (only the lightest and heaviest loads were applied) over another week. The main findings revealed that (I) the reliability of the F-V relationship parameters was very high and generally of comparable magnitude for both the multiple- [coefficient of variation (CV) range 1.91-3.94%; intraclass correlation coefficient (ICC) range 0.72-0.99] and two-point methods [CV range 1.41-4.62%; ICC range 0.76-0.95], (II) the magnitude of the same parameters obtained from both methods was highly correlated (r > 0.80), and (III) the P0 assessed from the multiple-point method was significantly lower than the obtained from the two-point method [P = 0.041; effect size (ES) 0.36] due to a significant decrease in F0 (P = 0.039; ES 0.41) with no significant differences observed for V0 (P = 0.570; ES - 0.15). These results support the two-point method as a reliable, valid, and fatigue-free procedure of assessing the muscle mechanical capacities through the F-V relationship.