Plant-based diets benefit aerobic performance and do not compromise strength/power performance: a systematic review and meta-analysis

Plant-based diets have emerged as athletic performance enhancers for various types of exercise. Therefore, the present study evaluated the effectiveness of plant-based diets on aerobic and strength/power performances, as well as on BMI of physically active individuals. This systematic review and meta-analysis was conducted and reported according to the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. A systematic search of electronic databases, including PubMed, Web of Science and SPORTDiscus, was performed. On the basis of the search and inclusion criteria, four and six studies evaluating the effects of plant-based diets on aerobic and strength/power performances in humans were, respectively, included in the systematic review and meta-analysis. Plant-based diets had a moderate but positive effect on aerobic performance (0·55; 95 % CI 0·29, 0·81) and no effect on strength/power performance (-0·30; 95 % CI -0·67, 0·07). The altogether analyses of both aerobic and strength/power exercises revealed that athletic performance was unchanged (0·01; 95 % CI -0·21, 0·22) in athletes who adopted plant-based diets. However, a small negative effect on BMI (-0·27; 95 % CI -0·40, -0·15) was induced by these diets. The results indicate that plant-based diets have the potential to exclusively assist aerobic performance. On the other hand, these diets do not jeopardise strength/power performance. Overall, the predicted effects of plant-based diets on physical performance are impactless, even though the BMI of their adherents is reduced.

Is physical performance affected by non-steroidal anti-inflammatory drugs use? A systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis aims to analyze the effects of ingesting non-steroidal anti-inflammatory drugs (NSAIDs) on physical performance, muscle strength and muscle damage in three different moments: immediately, 24 and 48 hours after resistance exercise practice.

METHODS

Relevant studies were researched in 3 databases (PubMed, Web of Science and SPORTDiscus) in April 2023. After excluding duplicates, the decision to include or exclude studies was made by two independent investigators in the following steps: (I) the study title; (II) the study abstract; and (III) the complete study manuscript. The following characteristics were recorded: (I) first author, (II) year of publication, (III) sample size, (IV) method of NSAIDs administration, (V) exercise protocol, and (VI) analyzed variable results. The studies selected were divided into trials that evaluated the effects of NSAIDs ingestion on performance indices of resistance exercise, endurance exercise and resistance training.

RESULTS

The meta-analysis, based only on resistance exercises, revealed that both performance and muscle strength were similar between placebo or NSAID treatment immediately and 24 hours after resistance exercise practice. An ergolytic effect was found 48 hours after resistance exercise (mean effect size (ES) = -0.42; 95% CI: -0.71, -0.12; p = 0.132), as well as reduced muscle strength (ES= -0.50; 95% CI: -0.83, -0.16; p = 0.072). Additionally, NSAID use did not prevent muscle waste as seen by the unchanged CK plasma concentration at all timetables.

CONCLUSION

The data of the present meta-analysis indicates that NSAID use is ineffective in improving resistance performance and muscle strength, as well as exercise recovery. When considering the practical application of using NSAIDs to improve exercise capacity and strength gains, the present data supports that consumption of analgesic drugs as an endurance performance enhancer or as a muscle anabolic must not be recommended.

Acute and chronic effects of physical exercise on IgA and IgG levels and susceptibility to upper respiratory tract infections: a systematic review and meta-analysis

This systematic review and meta-analysis aimed at evaluating acute and chronic effects of physical exercise on IgA and IgG levels, as well as its relationship with the susceptibility to develop upper respiratory tract infections (URTI). This systematic review and meta-analysis was conducted and reported in accordance with PRISMA statement. A systematic search of PubMed, Web of Science, and EMBASE was performed in July 2020. This systematic review and meta-analysis included studies in which participants performed acute exercise or chronic physical training and were subjected to analyses of URTI incidence and concentrations of IgA and IgG. The selected studies for systematic review were divided into the following three groups: (I) trials that evaluated the effects of acute exercise in sedentary subjects, (II) trials that evaluated the effects of acute exercise in athletes/trained individuals, and (III) trials that evaluated the effects of chronic physical training on the incidence of URTI, as well as on the levels of IgA and IgG. Acute exercise increases the IgA levels in trained subjects but does not affect its levels in untrained subjects. Such increase in IgA levels induced by acute exercise is greater in trained individual that performed ultramarathon. On the other hand, chronic physical training reduces IgA levels in both trained and untrained subjects, does not change IgA levels in non-military subjects, besides from not affecting IgG levels. The present systematic review and meta-analysis indicates that acute exercise positively influences IgA levels in trained individuals, being this effect pronounced when a strenuous exercise such as ultramarathon is executed. Chronic physical training, in turn, does not affect IgG levels.