Caffeine ingestion can improve performance across a variety of exercise modalities but can also elicit negative side effects in some individuals. Thus, there is a growing interest in the use of caffeine mouth rinse solutions to improve sport and exercise performance while minimizing caffeine’s potentially adverse effects. Mouth rinse protocols involve swilling a solution within the oral cavity for a short time (e.g., 5–10 s) before expectorating it to avoid systemic absorption. This is believed to improve performance via activation of taste receptors and stimulation of the central nervous system. Although reviews of the literature indicate that carbohydrate mouth rinsing can improve exercise performance in some situations, there has been no attempt to systematically review the available literature on caffeine mouth rinsing and its effects on exercise performance. To fill this gap, a systematic literature search of three databases (PubMed, SPORTDiscus, and Web of Science) was conducted by two independent reviewers. The search resulted in 11 randomized crossover studies that were appraised and reviewed. Three studies found significant positive effects of caffeine mouth rinsing on exercise performance, whereas the remaining eight found no improvements or only suggestive benefits. The mixed results may be due to heterogeneity in the methods across studies, interindividual differences in bitter tasting, and differences in the concentrations of caffeine solutions. Future studies should evaluate how manipulating the concentration of caffeine solutions, habitual caffeine intake, and genetic modifiers of bitter taste influence the efficacy of caffeine mouth rinsing as an ergogenic strategy.

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Ehlert, A and Wilson, PB. A systematic review of golf warm-ups: behaviors, injury, and performance. J Strength Cond Res 33(12): 3444–3462, 2019—Previous literature has demonstrated that warm-ups have the potential to increase physical performance and reduce risk of injury. Warm-ups before golf may have a similar result, but a systematic evaluation of their effects in golf is currently lacking. Three electronic databases (PubMed, SPORTDiscus, and Web of Science) were systematically searched to address 3 primary research questions: (a) What are the current warm-up behaviors of golfers?; (b) Is there an association between warm-up behaviors and golf-related injury?; and (c) What are the effects of various warm-up protocols on measures of golf performance? Twenty-three studies (9 observational and 14 experimental) were identified that included data on warm-ups before golf participation. Overall, the current data suggest that many golfers either do not warm-up regularly or perform a warm-up that is short in duration. Studies on the association between warm-up behaviors and golf-related injury were mixed and inconclusive. Experimental studies suggest that a variety of warm-up methods may be beneficial for golf performance. Specifically, dynamic warm-ups and those with resistance exercise tended to enhance measures of performance, whereas static stretching was inferior to other methods and potentially detrimental to performance. Overall, the results of this systematic review suggest that various warm-up protocols (with the exception of static stretching) may enhance golf performance, but observational data suggest many golfers do not regularly perform them. More data are needed on the warm-up behaviors of competitive golfers, the impact of warm-up behaviors on golf-related injury, and to further identify effective warm-up methods for enhancing golf performance.

Clubhead speed (CHS) is a commonly assessed golf performance measure and has been demonstrated to increase in response to physical training. Knowledge of the physical attributes that correlate with CHS will aid in developing effective testing and training protocols for golfers. Thus, the purpose of this review was to identify studies that evaluated the correlation between physical attributes and CHS and synthesise the correlation coefficients using three-level meta-analytic methods. Physical attributes were categorised first by general physical attribute categories. Pooled correlations were also estimated for specific attributes (e.g. jump height, body mass) that were evaluated across three or more studies. The results suggested that CHS had the strongest correlations with measures of upper body power/explosiveness (r = 0.

INTRODUCTION: Fatigue is a common problem in aviation. The identification of efficacious fatigue countermeasures is crucial for sustaining flight performance during fatigue-inducing operations. Stimulants are not recommended for consistent use, but are often implemented during flight operations with a high risk of fatigue. As such, it is important to evaluate the efficacy of approved stimulants for sustaining flight performance, alertness, and mood.METHODS: Four electronic databases (PubMed, PsycInfo, SPORTDiscus, Web of Science) were systematically searched to identify research on the effects of caffeine, dextroamphetamine, and modafinil during simulated or in-flight operations.RESULTS: There were 12 studies identified that assessed the effects of at least 1 stimulant. Overall, dextroamphetamine and modafinil were effective for sustaining flight performance and pilot mood during extended wakefulness. Results with caffeine were inconsistent.DISCUSSION: Dextroamphetamine and modafinil appear to sustain flight performance and mood during extended wakefulness. However, most studies have used flight simulators and short operation durations. Additional research is needed in realistic settings and during longer duration operations. Caffeines effects were inconsistent across studies, possibly due to differences in study methodology or individual caffeine responses. Despite fatigue being a common problem in civilian aviation as well, only one study in this review included civil aviators. More research should be conducted on the effects of caffeine during civil operations.CONCLUSION: Dextroamphetamine and modafinil appear to be effective fatigue countermeasures but should be further evaluated in more ecologically valid settings. The effects of caffeine are unclear at this time and should continue to be evaluated.Ehlert AM, Wilson PB. Stimulant use as a fatigue countermeasure in aviation. Aerosp Med Hum Perform. 2021; 92(3):190200.