Seasonal variability in physiological strain

Squash is a physiologically demanding sport (Northcote et al., 1986). Exercise heart rates of 162 beats/min have been reported (Blanksby et al., 1980) during “A” grade matches of 40 minutes duration in mild conditions (air temperature < 22°C, relative humidity < 60%). In 90-minute matches, elite players can exhibit sweat losses of 2 l and increases in rectal temperature of 1.6°C (Noakes et al., 1982). Oxygen uptakes from 2 to 4 l/min have been estimated for the sport (Durnin and Passmore, 1967).