Isometric and isokinetic testing of lifting strength of males in teamwork

Abstract

Additivity of static (isometric) and dynamic (isokinetic) strengths for teams of two and three males was evaluated. Six healthy college students participated in the laboratory experiment. The isometric strength evaluations consisted of four standard measures: arm, stooped back, leg, and composite, while the dynamic lift strength and dynamic back extension strength were used in isokinetic strength testing. In addition to individual strengths, the two-man strengths (15 teams for each of the six strengths) and the three-man strengths (20 teams for each of the six strengths) were tested. With the exception of the isometric leg strength for the team of two, and the isometric arm strength for the team of three, the team strengths were significantly lower (P<0·01) than the respective sums of the individual strengths of team members. On the average, the isometric strengths were approximately 94% of the sums of corresponding individual strengths for the team of two males. For the team of three males, the team isometric strengths averaged only 90% of the sum of individual strengths, with the exception of arm strength. The isokinetic strengths for the teams of two and three males accounted only for about 68 and 58% of the respective sums. The above results, indicating that human isometric and isotonic lifting strengths are not additive, suggest that the lifting capability of males in teamwork would be reduced as the number of team members increases.

Keywords:

• Strength
• Lifting
• Teamwork
• Testing