Article Text
Abstract
Data from cycling based protocols demonstrate that high-intensity interval training (HIT) is a more efficient mode of exercise training compared with traditional moderate-intensity continuous (CONT) approaches. The use of cycling based protocols is methodologically advantageous as total work done can be quantified by measuring subject's power output while pedalling on a cycle ergometer. However, examining the efficacy of HIT vs CONT running is more challenging as measurements of heart rate per se may not always reflect energy production. It may therefore be more accurate to prescribe, quantify and match exercise intensity during HIT and CONT running by matching protocols for average velocity corresponding to a particular %VO2max. The aim of the current study was to develop and match laboratory-based HIT and CONT running protocols for energy expenditure, average intensity, duration and distance run. Eight recreationally active men performed two running protocols consisting of HIT (6×3 min 90% VO2max interspersed with 6×3 min active recovery at 50% VO2max with 7-min warm-up and cool-down at 70% VO2max) and CONT (50 min continuous running exercise at 70% VO2max). Protocols were matched for average intensity (70% VO2max), duration (50 min) and distance run (9843±494 m). There was no difference (p>0.05) in average heart rate (88±3% HRmax vs 87±3% HRmax), average VO2 (71±6% VO2max vs 73±4% VO2max), total VO2 (162±16 litres vs 166±27 litres) or energy expenditure (811±83 kcal vs 832±136 kcal) between HIT and CONT protocols, respectively. Although ratings of perceived exertion were higher (p<0.05) during HIT compared to CONT (14±1 vs 13±1), HIT was characterised by higher ratings of perceived enjoyment (p<0.05) (88±6 vs 61±12). To the authors' knowledge, this is the first study to have matched HIT and CONT running for all the aforementioned variables. These data provide a controlled experimental model to study the efficacy of HIT vs CONT running. Furthermore, HIT is perceived as more enjoyable than CONT which may have implications for improving exercise adherence in individuals undertaking exercise training to improve human health and/or performance.