Modified sprint interval training protocols. Part II. Psychological responses

Abstract

Sprint-interval training (SIT) is a viable method to improve health and fitness. However, researchers have questioned the utility of SIT because of its strenuous nature. The current study aimed to determine if manipulating the sprint and recovery duration, while maintaining the 1:8 work to rest ratio, could uncover a more favourable SIT protocol. Nine healthy active males (age, 23.3 ± 3.0 years; body mass index, 22.4 ± 2.2 kg·m −2 ; maximal oxygen consumption, 48.9 ± 5.

Decreasing sprint duration from 20 to 10 s during reduced-exertion high-intensity interval training (REHIT) attenuates the increase in maximal aerobic capacity but has no effect on affective and perceptual responses

“…training) modifies the acute responses. Our finding that REHIT does not result in negative affect directly post-exercise is in contrast to longer SIT protocols with more sprints (Townsend et al, 2017). Conversely it is in line with Townsend's finding that shorter and, if sprint duration is kept constant, fewer sprints have less of an impact on affective responses.…”

“…We have recently provided preliminary data suggesting that a minimum of two sprint repetitions within a training session is required in order to improve VȮ2max (Songsorn et al, 2016;Songsorn et al, 2017;. Reducing the sprint duration in the REHIT protocol would do little to reduce the total training time (the bulk of each training session is spent on the lowintensity warm-up and recovery periods), but if the resulting protocol remains effective at improving VȮ2max it could be beneficial by reducing potential negative affective responses or perceived exertion (Townsend et al, 2017). However, in the present study we demonstrate that reducing the sprint duration from 20 s to 10 s attenuates the efficacy of the REHIT protocol at improving VȮ2max, and we therefore propose that the original protocol involving 20-s sprints remains the protocol of choice.…”

“…It follows that if sprint duration in the REHIT protocol can be reduced further without affecting the associated improvements in VȮ2max, the protocol would be perceived as less unpleasant and more tolerable. Recent findings by Townsend et al (2017) suggest that reducing sprint duration may attenuate negative affective responses to SIT. This in turn could potentially lead to better uptake of, and adherence to, SIT as a viable alternative exercise intervention for reducing risk of noncommunicable disease (Rhodes & Kates, 2015).…”

Modified sprint interval training protocols. Part I. Physiological responses

“…Nevertheless, the significant improvements in body composition following SIT (Whyte et al 2010;MacPherson et al 2011;Hazell et al 2014a) cannot be attributed to EE alone, but rather the potential combination of an elevated metabolic rate, greater suppression of appetite (Hazell et al 2016), and increased fat oxidation (Chan and Burns 2013) among other factors that facilitate the energy deficit required for fat loss. SIT protocols with shorter work bouts may also elicit more favourable psychological responses compared with traditional 30-s SIT, which can lead to improved exercise involvement and adherence (Townsend et al 2017). Future studies should investigate if training regimens involving these modified SIT protocols can promote similar benefits as traditional SIT, and establish the minimum dose of exercise required to achieve these results.…”

“…This appears logical as ϳ45% of the total work during a 30-s sprint is performed within the first 10 s (Bogdanis et al 1996) and as little as 4 s of repeated sprint running activates signaling pathways associated with mitochondrial remodeling in muscle (Serpiello et al 2012). As detailed in our companion article (Townsend et al 2017), shorter work bouts may also be more psychologically appealing given their ability to improve exercise-related parameters such as affect, self-efficacy, and enjoyment.…”