The Effects of Alcohol Consumption on Recovery Following Resistance Exercise: A Systematic Review

Effectiveness of Recovery Strategies After Training and Competition in Endurance Athletes: An Umbrella Review

BACKGROUND

Recovery strategies are used to enhance performance and reduce injury risk in athletes. In previous systematic reviews, individual recovery strategies were investigated to clarify their effectiveness for mixed groups of athletes. However, the current evidence is ambiguous, and a clear overview of (training) recovery for endurance athletes is still lacking.

METHODS

We conducted an umbrella review based on a literature search in PubMed, Cochrane Database of Systematic Reviews, and Web of Science. Reviews published in English and before December 2022 were included. Systematic reviews and meta-analyses were eligible if they investigated the effectiveness of one or more recovery strategies compared with a placebo or control group after a training session in endurance athletes.

RESULTS

Twenty-two reviews (nine systematic reviews, three meta-analyses, and ten systematic reviews with meta-analyses included) met the inclusion criteria. In total, sixty-three studies with 1100 endurance athletes were included in our umbrella review. Out of the sixty-three studies, eight provided information on training recovery time frame for data synthesis. Among them, cryotherapy and compression garments showed positive effects, while applying massage showed no effect. In general, none of the included recovery strategies showed consistent benefits for endurance athletes.

CONCLUSION

There is no particular recovery strategy that can be advised to enhance recovery between training sessions or competitions in endurance athletes. However, individual studies suggest that compression garments and cryotherapy are effective training recovery strategies. Further research should improve methodology and focus on the different time courses of the recovery process.

REGISTRATION

The review protocol was registered with the International Prospective Register of Systematic Reviews with the number CRD42021260509.

Excessive Ethanol Intake in Mice Does Not Impair Recovery of Torque after Repeated Bouts of Eccentric Contractions

PURPOSE

Alcoholics develop muscle atrophy and weakness from excessive ethanol (EtOH) intake. To date, most research has examined outcomes of alcohol-induced atrophy and weakness under basal or unstressed conditions despite physical stress being a normal occurrence in a physiological setting. Therefore, this study set out to determine if recovery of torque is impaired after repetitive bouts of physical stress in skeletal muscle during excessive short-term (experiment 1) and long-term (experiment 2) EtOH consumption.

METHODS

Twenty male and female mice were assigned to receive either 20% EtOH in their drinking water or 100% water. Short- and long-term consumption was predetermined to be EtOH intake starting at 4 and 26 wk, respectively. Anterior crural muscles performed repeated bouts of physical stress using in vivo eccentric contractions, with tetanic isometric torque being measured immediately pre- and postinjury. A total of 10 bouts were completed with 14 d between each bout within bouts 1-5 (experiment 1) and bouts 6-10 (experiment 2), and 12 wk between bouts 5 and 6.

RESULTS

Mice consuming EtOH had blood alcohol concentrations up to 270 mg·dL -1 . In experiment 1, five bouts of eccentric contractions did not reduce recovery of torque, regardless of sex or EtOH treatment ( P ≥ 0.173). Similarly, in experiment 2, preinjury torques did not differ from day 14 values regardless of sex or treatment ( P ≥ 0.322). However, there was a group effect in female mice for bouts 6 and 10 during experiment 2, with female EtOH mice being weaker than controls ( P ≤ 0.002).

CONCLUSIONS

Excessive short- or long-term EtOH misuse in a mouse model did not affect the muscle's ability to regain strength after repeated bouts of eccentric contractions, suggesting that EtOH may not be as detrimental to recovery as once predicted.

Understanding the role of smoking and chronic excess alcohol consumption on reduced caloric intake and the development of sarcopenia

This narrative review provides mechanistic insight into the biological link between smoking and/or chronic excess alcohol consumption, and increased risk of developing sarcopenia. Although the combination of excessive alcohol consumption and smoking is often associated with ectopic adipose deposition, this review is focused on the context of a reduced caloric intake (leading to energy deficit) that also may ensue due to either lifestyle habit. Smoking is a primary cause of periodontitis and chronic obstructive pulmonary disease that both induce swallowing difficulties, inhibit taste and mastication, and are associated with increased risk of muscle atrophy and mitochondrial dysfunction. Smoking may contribute to physical inactivity, energy deficit via reduced caloric intake, and increased systemic inflammation, all of which are factors known to suppress muscle protein synthesis rates. Moreover, chronic excess alcohol consumption may result in gut microbiota dysbiosis and autophagy-induced hyperammonemia, initiating the up-regulation of muscle protein breakdown and down-regulation of muscle protein synthesis via activation of myostatin, AMPK and REDD1, and deactivation of IGF-1. Future research is warranted to explore the link between oral healthcare management and personalised nutrition counselling in light of potential detrimental consequences of chronic smoking on musculoskeletal health outcomes in older adults. Experimental studies should investigate the impact of smoking and chronic excess alcohol consumption on the gut-brain axis, and explore biomarkers of smoking-induced oral disease progression. The implementation of behavioural change interventions and health policies regarding smoking and alcohol intake habits may mitigate the clinical and financial burden of sarcopenia on the healthcare system.