Investigation Into The Effect Of Warm Up On Intermittent Sprint Performance

[Truncated abstract] This PhD thesis consists of three separate but linked studies that focus on the concept of warm-up (WUP). While WUP is regularly performed prior to exercise by many athletes, its effect on subsequent exercise performance is equivocal. While there are many reasons for varying results between studies, it is possible that the intensity of WUP plays an important role in the outcome of subsequent exercise performance. Therefore, the aim of the first study was to investigate the effect of various WUP intensities (all based around individual lactate thresholds) on subsequent intermittent sprint performance (ISP), as well as the first sprint of ISP. A second aim of this first study was to determine which temperature (muscle; Tmu, rectal; Tre or body; Tb) best correlated with exercise performance (total work, power output of the first sprint and percentage work and power decrement). Results from this first study found no significant differences (P > 0.05) between any of the WUP conditions for any performance variable assessed. There was however, a tendency (ES {601} 0.5) for improved first sprint and ISP after a WUP that was performed at an intensity midway between lactate inflection (LI) and anaerobic threshold (also known as lactate threshold: LT). Further, there were no significant correlations between Tmu, Tre, or Tb assessed immediately after each WUP condition and any of the performance measures. ... The third study aimed to investigate the effect of an active WUP (performed at an intensity determined from study one) on prolonged ISP (80 min), as well as the first sprint of prolonged ISP, performed in hot and humid environmental conditions (35oC, 50% RH), compared to cooler conditions (~20-25oC, 20-40% RH). This study also assessed the effects of an active WUP compared to a passive WUP on 80 min of ISP undertaken in the heat (35oC, 50% RH). The only significant result for this study was represented by significantly improved peak power for the first sprint of prolonged IPS following passive WUP, compared to both active WUP conditions. Results from this study suggest that the main benefits of WUP are derived from temperature-related effects. Moreover, similar results for ISP performance following active compared to passive WUP may be explained by the following: (1) subjects used a pacing strategy throughout the exercise protocol; (2) the initial sprints performed following passive WUP provided similar effects to an active WUP over the period of prolonged exercise; (3) the effects of active and passive WUP diminish in a similar manner over the course of prolonged ISP, or (4) the metabolic and energy consequences of prolonged ISP override any benefits associated with WUP. Finally, environmental conditions did not have an effect on prolonged ISP or the first sprint of ISP that was preceded by an active WUP. These results may be related to core temperature values that did not reach critical levels proposed to impair exercise performance during exercise in hot and humid environmental conditions. Further studies are needed to investigate the effect of different WUP intensities (based on lactate thresholds) to those used in these studies on subsequent ISP in order to determine if a significant effect can be elicited. Of importance, a power analyses needs to be determined in order to make sure that participant numbers are adequate.