Physiological and psychological determinants of whole-body endurance exercise following short-term sustained operations with partial sleep deprivation

Abstract

PurposeThe study examined the effects of short-term field-based military training with partial sleep deprivation on whole-body endurance performance in well-trained individuals.MethodsBefore and after a 2-day sustained operations (SUSOPS), 14 cadets performed a 15-min constant-load cycling at 65% of peak power output (PPO; CLT65), followed by an exhaustive constant-load trial at 85% of PPO (CLT85). Physiological [oxygen uptake (O2), heart rate (HR), mean arterial pressure (MAP), cardiac output (CO), and regional oxygenation (TOI) in the frontal cerebral cortex and vastus lateralis muscle] and psychological [effort perception (RPE), affective valence (FS), and perceived activation (FAS)] variables were monitored during exercise.ResultsSUSOPS reduced time to exhaustion in CLT85 by 29.1% (p = 0.01). During the CLT65 trial, SUSOPS potentiated the exercise-induced elevations in O2 and HR (p < 0.05), and blunted MAP (p = 0.001). CO did not differ between trials. Yet, towards the end of both CLT85 trials, CO tended to decline (p ≤ 0.08); a response that occurred at an earlier stage in the SUSOPS trial. During CLT65, SUSOPS altered neither cerebral nor muscle TOI. The SUSOPS CLT85 trial, however, was terminated at similar leg-muscle deoxygenation (p > 0.05) and lower prefrontal cortex deoxygenation (p < 0.01). SUSOPS increased RPE at submaximal intensities (p = 0.05), and suppressed FAS and FS throughout (p < 0.01).ConclusionsThe present findings indicate, therefore, that a brief period of military sustained operations with partial sleep deprivation augment cardiorespiratory and psychological strain, limiting high-intensity endurance capacity.

Kayaking performance is altered in mentally fatigued young elite athletes

“…It seems that mental fatigue influences negatively, at least in kayaking, the frequency of the actions. Those results are in line with a previous study 28 showing that a combination of physical and cognitive fatigue affected cadence during a cycling time to exhaustion test.…”

The effects of a single night of complete and partial sleep deprivation on physical and cognitive performance: A Bayesian analysis

“…For example, Oliver et al (2009) suggested that a distance test, such as the one used in the current study, might have a smaller signal to noise ratio than incremental exercise tests which were used by Vaara et al (2018) and Goodman et al (1989). These differences are potentially explained by the altered perception of effort experienced following sleep deprivation (Keramidas, Gadefors, Nilsson, & Eiken, 2018), given that incremental tests only require a relatively short period of discomfort in contrast to distance tests. In the current study aerobic performance appears to be impaired due to a consistently lower power output throughout rather than an alteration in pacing strategy (see Fig.…”

“…Across all outcome measures we found considerable individual variation in responses, i.e. not 391 all participants appear to be negatively impacted by sleep deprivation, a trait that is common 392 within similar studies (Keramidas et al, 2018;Oliver et al, 2009). This is an important issue 393 and one that potentially explains some of the conflicting results within the existing literature 394 as it will likely lead to skewed data, which may mask any effects using traditional NHST.…”

The Effects of Sleep Loss on Military Physical Performance

“…The authors attributed these changes in physiological responses to possible alterations in glycogen metabolism and metabolic rate that occur as a result of SD. Keramidas et al [37] reported alterations in aerobic capacity and cardiorespiratory responses during high-intensity constantload cycling following a 51 h trial where participants attained a total of 5 h sleep. Participants performed two constant-load trials, one trial at 65% and another at 85% of their peak power output (PPO).…”