Effect of the Depth of Cold Water Immersion on Sleep Architecture and Recovery Among Well-Trained Male Endurance Runners

Abstract

Introduction: The aim of the present study was to investigate the effect of the depth of cold water immersion (CWI) (whole-body with head immersed and partial-body CWI) after high-intensity, intermittent running exercise on sleep architecture and recovery kinetics among well-trained runners.Methods: In a randomized, counterbalanced order, 12 well-trained male endurance runners (V.O2max = 66.0 ± 3.9 ml·min−1·kg−1) performed a simulated trail (≈18:00) on a motorized treadmill followed by CWI (13.3 ± 0.2°C) for 10 min: whole-body immersion including the head (WHOLE; n = 12), partial-body immersion up to the iliac crest (PARTIAL; n = 12), and, finally, an out-of-water control condition (CONT; n = 10). Markers of fatigue and muscle damage—maximal voluntary isometric contraction (MVIC), countermovement jump (CMJ), plasma creatine kinase [CK], and subjective ratings—were recorded until 48 h after the simulated trail. After each condition, nocturnal core body temperature (Tcore) was measured, whereas sleep and heart rate variability were assessed using polysomnography.Results: There was a lower Tcore induced by WHOLE than CONT from the end of immersion to 80 min after the start of immersion (p < 0.05). Slow-wave sleep (SWS) proportion was higher (p < 0.05) during the first 180 min of the night in WHOLE compared with PARTIAL. WHOLE and PARTIAL induced a significant (p < 0.05) decrease in arousal for the duration of the night compared with CONT, while only WHOLE decreased limb movements compared with CONT (p < 0.01) for the duration of the night. Heart rate variability analysis showed a significant reduction (p < 0.05) in RMSSD, low frequency (LF), and high frequency (HF) in WHOLE compared with both PARTIAL and CONT during the first sequence of SWS. No differences between conditions were observed for any markers of fatigue and muscle damage (p > 0.05) throughout the 48-h recovery period.Conclusion: WHOLE reduced arousal and limb movement and enhanced SWS proportion during the first part of the night, which may be particularly useful in the athlete's recovery process after exercise. Future studies are, however, required to assess whether such positive sleep outcomes may result in overall recovery optimization.

Functional Impact of Post-exercise Cooling and Heating on Recovery and Training Adaptations: Application to Resistance, Endurance, and Sprint Exercise

“…Since muscle glycogen stores are usually fully replenished within 24-48 h after prolonged endurance exercise when carbohydrate is provided adequately [99], local cooling or heating following glycogen-depleting exercise would unlikely affect performance of endurance exercise bouts performed 1-2 days after the initial bout. CWI (8-15 °C for 10-15 min) did not influence the later post-exercise recovery of muscle strength (peak isokinetic torque and MVIC, 24-48 h post-exercise) and jump performance [drop jump (DJ), 24-48 h postexercise; CMJ, 24-48 h post-exercise; triple hop, 24 h post-exercise] [94,97,100,101]. In these studies, these outcomes were only slightly impaired directly after the initial endurance session and were fully recovered within 24-48 h. Future experiments could focus on the impact of post-exercise cooling in extreme endurance activities (such as mountain ultra-marathon) where neuromuscular function is substantially impaired directly after exercise [102,103] and required several days to be fully recovered [103].…”

“…23 °C and 43% RH Crossover design: CWI: 15 °C for 15 min immediately or 3 h post-Ex. CON: 15 min PR immediately after Ex Higher number of shuttles completed (Yo-Yo intermittent recovery test) @ 24 h post-Ex in CWI (immediately > 3 h post-Ex) versus CON ↑ of CWI (immediately post-HIIE) on shuttle test performance @ 24 h Chauvineau et al [ 101 ] Well trained runners (12 M, 28 Y) Running: Simulated trail run for 48 min 21 °C and 44% RH Crossover design: CWI (whole body including the head): 13 °C for 10 min. CWI (up to the waist): 13 °C for 10 min.…”

“…CWI (8–15 °C for 10–15 min) did not influence the later post-exercise recovery of muscle strength (peak isokinetic torque and MVIC, 24–48 h post-exercise) and jump performance [drop jump (DJ), 24–48 h post-exercise; CMJ, 24–48 h post-exercise; triple hop, 24 h post-exercise] [ 94 , 97 , 100 , 101 ]. In these studies, these outcomes were only slightly impaired directly after the initial endurance session and were fully recovered within 24–48 h. Future experiments could focus on the impact of post-exercise cooling in extreme endurance activities (such as mountain ultra-marathon) where neuromuscular function is substantially impaired directly after exercise [ 102 , 103 ] and required several days to be fully recovered [ 103 ].…”

Athlete, coach and practitioner knowledge and perceptions of post-exercise cold-water immersion for recovery: a qualitative and quantitative exploration

“…Therefore, a greater immersion depth might be successful by way of greater hydrostatic pressures. Indeed, recent work from Chauvineau et al [16] suggests whole body immersion (including head immersion) might benefit recovery through improved sleep architecture, reducing arousal and limb movements through the first part of the night. However, no difference was noted between whole and partial body CWI for markers of fatigue and muscle damage.…”

“…Efficacy of CWI for post-exercise recovery has previously been considered equivocal [10] likely due to inconsistency in CWI protocols, with different temperatures [11][12][13], durations [14,15], depths [16,17] and even time applied after exercise [18] being utilised in research and applied practice [19]. Meta-analyses suggest a protocol of 10-15 °C for 10-15 min [20] can effectively promote recovery.…”