Maximal aerobic capacity can be increased by enhancing performers' expectancies.

Abstract

Maximum aerobic capacity (VO2max) is widely accepted as the best measure of cardiovascular fitness and aerobic power. The present study investigated whether enhancing participants' performance expectancies through positive social-comparative feedback would increase VO2max. Participants were experienced runners who regularly ran for exercise or competitively. All participants completed two VO2max tests within a 2-week period at similar times of the day. Before the second test, enhanced expectancy group participants were informed that their aerobic capacity on the first test was above the group average, whereas control group participants were told the second test was for validation purposes. Measurements taken were relative to VO2max, as well as pulmonary ventilation, respiratory exchange ratio, heart rate, and ratings of perceived exertion. The enhanced expectancy group demonstrated a significant increase (+3.28%) in VO2max from test 1 (61.1±2.8 mL·kg-1·min-1) to test 2 (63.7±2.9 mL·kg-1·min-1, P=0.007), whereas the control group's VO2max decreased significantly (-4.11%, test 1 =59.4±2.9 mL·kg-1·min-1, test 2 =57.8±2.3 mL·kg-1·min-1, P=0.027). No group differences were found with respect to other performance measures (pulmonary ventilation P=0.22, heart rate P=0.97, respiratory exchange ratio P=0.11, rate of perceived exertion P=0.13). The results show that maximum aerobic capacity is, in part, a function of the performer's self-efficacy expectations. These findings add to the increasing evidence demonstrating social-cognitive-affective influences on (maximum) motor performance.