The effect of high ambient temperature on the responses to a controlled football simulation

Introduction The performance characteristics of match-play in football, such as the number of sprints and distance covered are thought to be reduced when ambient temperature is high (Ozgunen et al. 2010). However, assessment of the extent of additional fatigue due to temperature is difficult owing to the voluntary nature of football activity. The present study demonstrates the responses to a controlled football match-play simulation (Stone et al. 2011) performed in contrasting mean ambient temperatures of 19 and 27 degrees (‘normal’ and ‘hot’, respectively). Methods Semi-professional, male University football players (n=13) were tested. The procedure was divided into identical six 16-min blocks of activity, comprising sprinting and controlled-speed walking, jogging and running with a 15-min break to replicate half-time. The total distance covered in each trial was 11.2km. Single-sprint performance over 15m was assessed through each 16-min block. Midway through each 16-min block, one bout of repeated sprint (RS) exercise (6 x 15m starting every 18 seconds) was also used. All sprints were made from a standing start. Heart rate (HR) and blood lactate were monitored through the whole procedure. Data were analysed using 2 way (time * temperature) repeated measures ANOVA and Bonferroni post hoc. Significance was accepted at P0.05). Discussion The ‘hot’ trial led to more fatigue and greater HR than the ‘normal’ condition. Sprint performance over 15-m was slower by around 3% in ‘hot’ vs. ‘normal’ conditions and, in keeping with the match-play data from Ozgunen et al. (2010), the decline in performance was only significant in the second half of the simulation. By controlling distance covered and using standard exercise intensities for all but the sprints, these data show the extent to which ambient temperature is likely to influence responses to football match play. Stone, K. et al. (2011). Int. J. Sports Physiol. & Perform. 6: 427 - 431. Ozgunen, K.T. et al. (2010). Scand. J. Med. Sci. Sports 20. (Suppl 3): 140-147