Effects of post-exercise cold-water immersion on performance and perceptive outcomes of competitive adolescent swimmers

PURPOSE

To evaluate the effects of repeated use of cold-water immersion (CWI) during a training week on performance and perceptive outcomes in competitive adolescent swimmers.

METHODS

This randomized-crossover study included 20 athletes, who received each intervention [CWI (14 ± 1 °C), thermoneutral water immersion (TWI) (27 ± 1 °C) as placebo, and passive recovery (PAS)] three times a week between the land-based resistance training and swim training. The interventions were performed in a randomized order with a 1-week wash-out period. We tested athletes before and after each intervention week regarding swim (100 m freestyle sprints) and functional performance (flexibility, upper and lower body power, and shoulder proprioception). We monitored athlete's perceptions (well-being, heaviness, tiredness, discomfort and pain) during testing sessions using a 5-item questionnaire. Athlete preferences regarding the interventions were assessed at the end of the study. We used generalized linear mixed models and generalized estimating equations for continuous and categorical variables, respectively (intervention x time).

RESULTS

We found a time effect for swim performance (p = .01) in which, regardless the intervention, all athletes improved sprint time at post-intervention compared to baseline. There was an intervention effect for pain (p = .04) and tiredness (p = .04), but with no significant post-hoc comparisons. We found no significant effects for other outcomes. All athletes reported a preference for CWI or TWI in relation to PAS.

CONCLUSION

The repeated use of CWI throughout a training week did not impact functional or swim performance outcomes of competitive adolescent swimmers. Perceptive outcomes were also similar across interventions; however, athletes indicated a preference for both CWI and TWI.

Influence of physical post-exercise recovery techniques on vagally-mediated heart rate variability: A systematic review and meta-analysis

In sports, physical recovery following exercise-induced fatigue is mediated via the reactivation of the parasympathetic nervous system (PNS). A noninvasive way to quantify the reactivation of the PNS is to assess vagally-mediated heart rate variability (vmHRV), which can then be used as an index of physical recovery. This systematic review and meta-analysis investigated the effects of physical recovery techniques following exercise-induced fatigue on vmHRV, specifically via the root mean square of successive differences (RMSSD). Randomized controlled trials from the databases PubMed, WebOfScience, and SportDiscus were included. Twenty-four studies were part of the systematic review and 17 were included in the meta-analysis. Using physical post-exercise recovery techniques displayed a small to moderate positive effect on RMSSD (k = 22, Hedges' g = 0.40, 95% confidence interval [CI] = 0.20-0.61, p = 0.04) with moderate heterogeneity. In the subgroup analyses, cold water immersion displayed a moderate to large positive effect (g = 0.75, 95% CI: 0.42-1.07) compared with none for other techniques. For exercise type, physical recovery techniques performed after resistance exercise (g = 0.69, 95% CI: 0.48-0.89) demonstrated a larger positive effect than after cardiovascular intermittent (g = 0.52, 95% CI: 0.06-0.97), while physical recovery techniques performed after cardiovascular continuous exercise had no effect. No significant subgroup differences for training status and exercise intensity were observed. Overall, physical post-exercise recovery techniques can accelerate PNS reactivation as indexed by vmHRV, but the effectiveness varies with the technique and exercise type.

What Parameters Influence the Effect of Cold-Water Immersion on Muscle Soreness? An Updated Systematic Review and Meta-Analysis

OBJECTIVE

Our objective was to determine the efficacy of cold-water immersion (CWI) on the management of muscle soreness to identify the impact of immersion time, water temperature, CWI protocol, and type of exercise on this outcome.

DESIGN

Intervention systematic review and meta-analysis.

SETTING

MEDLINE/PubMed, Embase, Central, and SPORTDiscus databases were searched from their earliest record to July 30, 2020. Only randomized controlled trials that assessed muscle soreness comparing CWI and control were included. Studies were pooled in different subgroups regarding the used protocol: water temperature (severe or moderate cold), immersion time (short, medium, or longer time), CWI protocol (intermittent or continuous application), and type of exercise (endurance or resistance exercise). Data were pooled in a meta-analysis and described as weighted mean difference (95% confidence interval, P < 0.05).

PARTICIPANTS

Athletes and nonathletes.

INTERVENTIONS

Cold-water immersion and control condition.

MAIN OUTCOME MEASURES

Muscle soreness.

RESULTS

Forty-four studies were included. For immediate effects, CWI was superior to control regardless of water temperature and protocol, and for short and medium immersion times and endurance exercises. For delayed effects, CWI was superior to control in all subgroups except longer immersions time.

CONCLUSIONS

This study suggests that CWI is better than control for the management of muscle soreness and water temperature and CWI protocol do not influence this result, but only short and medium immersions times presented positive effects. Aiming immediate effects, the best results suggest CWI application only after endurance exercises, while delayed effect CWI was superior both after endurance and resistance exercises.

Physical therapy interventions for the treatment of delayed onset muscle soreness (DOMS): Systematic review and meta-analysis

OBJECTIVE

To evaluate the impact of interventions on pain associated with DOMS.

DATA SOURCES

PubMed, EMBASE, PEDro, Cochrane, and Scielo databases were searched, from the oldest records until May/2020. Search terms used included combinations of keywords related to "DOMS" and "intervention therapy".

ELIGIBILITY CRITERIA

Healthy participants (no restrictions were applied, e.g., age, sex, and exercise level). To be included, studies should be: 1) Randomized clinical trial; 2) Having induced muscle damage and subsequently measuring the level of pain; 3) To have applied therapeutic interventions (nonpharmacological or nutritional) and compare with a control group that received no intervention; and 4) The first application of the intervention had to occur immediately after muscle damage had been induced.

RESULTS

One hundred and twenty-one studies were included. The results revealed that the contrast techniques (p = 0,002 I² = 60 %), cryotherapy (p = 0,002 I² = 100 %), phototherapy (p = 0,0001 I² = 95 %), vibration (p = 0,004 I² = 96 %), ultrasound (p = 0,02 I² = 97 %), massage (p < 0,00001 I² = 94 %), active exercise (p = 0,0004 I² = 93 %) and compression (p = 0,002 I² = 93 %) have a better positive effect than the control in the management of DOMS.

CONCLUSION

Low quality evidence suggests that contrast, cryotherapy, phototherapy, vibration, ultrasound, massage, and active exercise have beneficial effects in the management of DOMS-related pain.

Submaximal Elastic Resistance Band Tests to Estimate Upper and Lower Extremity Maximal Muscle Strength

Muscle strength assessment is fundamental to track the progress of performance and prescribe correct exercise intensity. In field settings, simple tests are preferred. This study develops equations to estimate maximal muscle strength in upper- and lower-extremity muscles based on submaximal elastic resistance tests. Healthy adults (n = 26) performed a maximal test (1 RM) to validate the ability of the subsequent submaximal tests to determine maximal muscle strength, with elastic bands. Using a within-group repeated measures design, three submaximal tests of 40%, 60%, and 80% during (1) shoulder abduction, (2) shoulder external rotation, (3) hip adduction, and (4) prone knee flexion were performed. The association between number of repetitions and relative intensity was modeled with both 1st and 2nd order polynomials to determine the best predictive validity. For both upper-extremity tests, a strong linear association between repetitions and relative intensity was found (R² = 0.97–1.00). By contrast, for the lower-extremity tests, the associations were fitted better with a 2nd order polynomial (R² = 1.00). The results from the present study provide formulas for predicting maximal muscles strength based on submaximal resistance in four different muscles groups and show a muscle-group-specific association between repetitions and intensity.

Futureproofing triathlon: expert suggestions to improve health and performance in triathletes

Background

Given the multi-modal nature of triathlon (swimming, cycling, running), training for a triathlon event has numerous potential health benefits including physical fitness. However, triathletes also have a high prevalence of health issues including overuse injury, illness, fatigue, and burnout. To address the ongoing prevalence of health issues, roundtable discussions were organized at the International Triathlon Union Science of Triathlon 2017 conference to develop strategic objectives deemed necessary to “futureproof triathlon”. Futureproofing as a concept serves to design new approaches and ways of thinking to reduce consequences in the future. In this case, the futureproof process aimed to develop key recommendations for triathlon.

Methods

This qualitative study had 22 participants including athletes, coaches, practitioners, academics, and policy makers who participated in roundtable discussions at the Science of Triathlon conference. Seven of these participants completed follow-up semi-structured interviews on the same topics. The data collected from the roundtable discussions and the semi-structured interviews was analyzed using thematic analysis.

Results

Five main themes were produced: “Critical appraisal and application of knowledge”; “Integrated approaches to developing, disseminating, and using research and expertise”; “Appropriate development and use of measures for monitoring training and recovery”; “Knowing your athletes and adopting holistic approaches to athlete/person-development”, and; “Challenging accepted cultural and sporting norms”. Participants indicated the need to reduce the knowledge gap between research and practice as well as a more collaborative approach to triathlon research development amongst coaches/practitioners and academics. It was stated that current monitoring tools require more research to determine which are most useful to informed decision making for coaches/practitioners. It was cautioned that data driven assessments should be used judiciously and be athlete centered. Triathlon as a sport should also have a greater focus on healthy participation and development of youth athletes.

Conclusions

A series of applied implications were developed based on these five themes as guiding principles for how to futureproof triathlon. Additionally, roundtable and interview participants who held varying positions and opinions within the sport of triathlon agreed that the unique challenge of training for and competing in a triathlon should not be forgotten in the futureproofing of the sport.