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Physiological Responses to Cold Water Immersion Following Cycling in the Heat

Shona L. Halson, Marc J. Quod, David T. Martin, Andrew S. Gardner, Tammie R. Ebert, and Paul B. Laursen

Cold water immersion (CWI) has become a popular means of enhancing recovery from various forms of exercise. However, there is minimal scientific information on the physiological effects of CWI following cycling in the heat.

Purpose:

To examine the safety and acute thermoregulatory, cardiovascular, metabolic, endocrine, and inflammatory responses to CWI following cycling in the heat.

Methods:

Eleven male endurance trained cyclists completed two simulated ~40-min time trials at 34.3 ± 1.1°C. All subjects completed both a CWI trial (11.5°C for 60 s repeated three times) and a control condition (CONT; passive recovery in 24.2 ± 1.8°C) in a randomized cross-over design. Capillary blood samples were assayed for lactate, glucose, pH, and blood gases. Venous blood samples were assayed for catecholamines, cortisol, testosterone, creatine kinase, C-reactive protein, IL-6, and IGF-1 on 7 of the 11 subjects. Heart rate (HR), rectal (Tre), and skin temperatures (Tsk) were measured throughout recovery.

Results:

CWI elicited a significantly lower HR (CWI: Δ116 ± 9 bpm vs. CONT: Δ106 ± 4 bpm; P = .02), Tre (CWI: Δ1.99 ± 0.50°C vs. CONT: Δ1.49 ± 0.50°C; P = .01) and Tsk. However, all other measures were not significantly different between conditions. All participants subjectively reported enhanced sensations of recovery following CWI.

Conclusion:

CWI did not result in hypothermia and can be considered safe following high intensity cycling in the heat, using the above protocol. CWI significantly reduced heart rate and core temperature; however, all other metabolic and endocrine markers were not affected by CWI.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 3 (2008): Issue 3 (Sep 2008)

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Hyperthermic Fatigue Precedes a Rapid Reduction in Serum Sodium in an Ironman Triathlete: A Case Report

Paul B. Laursen, Greig Watson, Chris R. Abbiss, Bradley A. Wall, and Kazunori Nosaka

Purpose:

To monitor the hydration, core temperature, and speed (pace) of a triathlete performing an Ironman triathlon.

Methods:

A 35-year-old experienced male triathlete participated in the Western Australian Ironman triathlon on December 1, 2006. The participant was monitored for blood Na+ concentration before the race (PRE), at the transitions (T1 and T2), halfway through the run (R21), and after the race (POST; 2hPOST). Core body temperature (T ; pill telemetry) was recorded continuously, and running speed (s3 stride sensor) was measured during the run.

Results:

The participant completed the race in 11 h 38 min, in hot conditions (26.6 ± 5.8°C; 42 ± 19% rel. humidity). His Tc increased from 37.0 to 38.6°C during the 57-min swim, and averaged 38.4°C during the 335-min bike (33.5 km·h-1). After running at 12.4 km·h-1 for 50 min in the heat (33.1°C), T increased to 39.4°C, before slowing to 10.0 km·h-1 for 20 min. T decreased to 38.9°C until he experienced severe leg cramps, after which speed diminished to 6 km·h-1 and T fell to 38.0°C. The athlete’s blood Na+ was constant from PRE to T2 (139-140 mEq·L-1, but fell to 131 mEq·L-1 at R21, 133 mEq·L-1 at POST, and 128 mEq·L-1at 2hPOST The athlete consumed 9.25 L of fuid from PRE to T2, 6.25 L from T2 to POST, and lost 2% of his body mass, indicating sweat losses greater than 15.5 L.

Conclusion:

This athlete slowed during the run phase following attainment of a critically high T and experienced an unusually rapid reduction in blood Na+ that preceded cramping, despite presenting with signs of dehydration.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 4 (2009): Issue 4 (Dec 2009)

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Evaluating Warm-Up Strategies for Elite Sprint Breaststroke Swimming Performance

Courtney J. McGowan, David B. Pyne, Kevin G. Thompson, and Ben Rattray

Purpose:

Targeted passive heating and completion of dryland-based activation exercises within the warm-up can enhance sprint freestyle performance. The authors investigated if these interventions would also elicit improvements in sprint breaststroke swimming performance.

Methods:

Ten national and internationally competitive swimmers (~805 FINA (Fédération internationale de natation) 2014 scoring points; 6 men, mean ± SD 20 ± 1 y; 4 women, 21 ± 3 y) completed a standardized pool warm-up (1550 m) followed by a 30-min transition phase and a 100-m breaststroke time trial. In the transition phase, swimmers wore a conventional tracksuit and remained seated (control) or wore tracksuit pants with integrated heating elements and performed a 5-min dryland-based exercise routine (combo) in a crossover design.

Results:

Performance in the 100-m time trial (control: 68.6 ± 4.0 s, combo: 68.4 ± 3.9 s, P = .55) and start times to 15 m (control: 7.3 ± 0.6 s; combo: 7.3 ± 0.6 s; P = .81) were not different between conditions. It was unclear (P = .36) whether combo (–0.12°C ± 0.19°C [mean ± 90% confidence limits]) elicited an improvement in core temperature maintenance in the transition phase compared with control (–0.31°C ± 0.19°C). Skin temperature immediately before commencement of the time trial was higher (by ~1°C, P = .01) within combo (30.13°C ± 0.88°C [mean ± SD]) compared with control (29.11°C ± 1.20°C). Lower-body power output was not different between conditions before the time trial.

Conclusions:

Targeted passive heating and completion of dryland-based activation exercises in the transition phase does not enhance sprint breaststroke performance despite eliciting elevated skin temperature immediately before time trial commencement.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 11 (2016): Issue 7 (Oct 2016)

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Increased Thermoregulatory Strain When Wearing an Upper Body Compression Garment During Moderate Exercise in Trained Older Adults

Iker Leoz-Abaurrea, Mikel Izquierdo, Miriam Gonzalez-Izal, and Roberto Aguado-Jiménez

The efficacy of the use of an upper body compression garment (UBCG) as an ergogenic aid to reduce thermoregulatory strain in older adults remains unknown. The aim of this study was to evaluate the effects of UBCG on thermoregulatory, cardiorespiratory, and perceptual responses during cycling in a temperate environment (~25 °C, 66% rh) in trained older adults. Twelve cyclists aged 66 ± 2 years performed an intermittent 1-hr cycling trial at 50% of the peak power output followed by 10 min of passive recovery. Participants were provided with either commercially available UBCG or a control garment in a randomized order. UBCG increased thermoregulatory strain during exercise, as indicated by a significantly higher core temperature (38.1 ± 0.3 °C vs. 37.9 ± 0.3 °C; p = .04), body temperature (36.9 ± 0.2 °C vs. 36.7 ± 0.2 °C; p = .01), and thermal sensation (8.0 ± 0.4 vs. 7.5 ± 1.0; p = .02). These results suggest that the use of UBCG in trained older adults does not reduce the thermoregulatory strain during moderate exercise.

Cover Journal of Aging and Physical Activity

In Journal of Aging and Physical Activity Volume 25 (2017): Issue 1 (Jan 2017)

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Hydration and Core Temperature in a Football Player during Preseason: A Case Study

Sandra Fowkes Godek and Arthur R. Bartolozzi

Cover International Journal of Athletic Therapy and Training

In International Journal of Athletic Therapy and Training Volume 9 (2004): Issue 4 (Jul 2004)

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Enhanced Decision Making and Working Memory During Exercise in the Heat With Crushed Ice Ingestion

Jacinta M. Saldaris, Grant J. Landers, and Brendan S. Lay

is generally reported that, like physiological performance, heat stress negatively affects cognitive function, with deleterious effects reported above a core temperature ( T core ) of 38.5°C. 5 Furthermore, heat removal from the brain is impaired due to lower cerebral blood flow and increased heat

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 15 (2020): Issue 4 (Apr 2020)

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The Physiological Strain Index Modified for Trained Heat-Acclimatized Individuals in Outdoor Heat

Christopher Byrne and Jason K.W. Lee

simple method of evaluating heat strain with potential for universal use. 3 The PSI combines normalized increases in core temperature (TC) and heart rate (HR) to produce an instantaneous measure of strain on a 0 to 10 scale. 2 , 3 The PSI has demonstrated validity in discriminating between levels of

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 14 (2019): Issue 6 (Jul 2019)

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Effect of a Cooling Kit on Physiology and Performance Following Exercise in the Heat

Cody R. Smith, Cory L. Butts, J.D. Adams, Matthew A. Tucker, Nicole E. Moyen, Matthew S. Ganio, and Brendon P. McDermott

Exercising in a hot environment increases hyperthermia, which can lead to heat exhaustion or exertional heat stroke. Exercise-induced hyperthermia can reach critical levels when the body’s internal (core) temperature exceeds 40°C. 1 If an individual suffers exertional heat stroke, lowering core

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 27 (2018): Issue 5 (Sep 2018)

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The Threshold Ambient Temperature for the Use of Precooling to Improve Cycling Time-Trial Performance

Steve H. Faulkner, Iris Broekhuijzen, Margherita Raccuglia, Maarten Hupperets, Simon G. Hodder, and George Havenith

can have an ergogenic effect. 7 , 8 This is thought to be due to a decrease in skin and/or core temperature before exercise starts, which increases the capacity for heat storage during exercise, and therefore, exercise is expected to be possible for a longer duration compared with no precooling

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 14 (2019): Issue 3 (Mar 2019)

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Efficacy of Cold Water Immersion Prior to Endurance Cycling or Running to Increase Performance: A Critically Appraised Topic

Connor A. Burton and Christine A. Lauber

Clinical Scenario Intense aerobic exercise can produce metabolic heat at a rate of 20 kilocalories per minute in elite athletes. Heat production, therefore, can equate to a core temperature (T c ) increase of 1°C every 5–7 min. 1 The rise in T c can challenge thermoregulation of the body and

Cover International Journal of Athletic Therapy and Training

In International Journal of Athletic Therapy and Training Volume 23 (2018): Issue 1 (Jan 2018)