Cardiovascular responses during recreational 5-a-side indoor-soccer

Summary 

The aims of this study were to examine the cardiovascular response to recreational 5-a-side indoor-soccer (5v5) matches (5v5 study, 5v5S, n=15) and to assess the validity of using heart rate (HR) to estimate oxygen uptake (VO₂) demands during actual game-play (validity study, VS, n=16) in young subjects (age 16.8±1.5 years). Game responses during 5v5S were assessed during 30min matches using short-range telemetry heart-rate monitors. In VS games (12min), VO₂ and HR were monitored with a portable gas analyser (K4b², COSMED, Rome, Italy). Individual HR–VO₂ relationships were determined from a laboratory treadmill run to exhaustion (VS) and a multistage shuttle running fitness test (5v5S) using K4b². Results showed that 5v5 elicits 83.5±5.4 and 75.3±11.2% of HR_peak and VO_2peak, respectively. Ninety-one percent of the playing time (30min) was spent at HR higher than 70% of HR_peak. In VS match, gas analyses revealed that only 71% of HR variance was explained by VO₂ variations. However, playing at approximately 70% of HR_peak elicited 51.6±11.2% of VO_2peak. Group actual versus predicted VO₂ values demonstrated no significant differences (p>0.05), however, large confidence limits were observed (+6.20 and −10.53mlkg⁻¹min⁻¹). These results show that HR and VO₂ responses to recreational 5v5 soccer in young athletes are similar to the exercise intensities recommended by ACSM for promoting cardiovascular health and suggest that HR is valid to prescribe and monitor aerobic intermittent exercise. These results also show that HR measures are acceptable for estimating VO₂ during intermittent exercise when assessing large groups, but show that large estimation errors can occur at the individual level.

Keywords: Soccer, Physical fitness, Heart rate, Intermittent exercise, Perceived exertion