One of the most promoted nutritional aids for athletes, caffeine, can improve cardiorespiratory and muscular endurance, movement velocity, and power during resistance training. It can also influence neurotransmitters for exertion and arousal.
However, side effects of consuming caffeine are observed at doses of 4–6 mg/kg and include headache, anxiety, insomnia, gastrointestinal complaints, etc.
A recent study published in Nutrients journal showed that rinsing your mouth with high doses of caffeine mouth rinse can improve muscular performance, allowing you to reap some of the benefits of caffeine while avoiding adverse effects associated with caffeine consumption.
Plenty of studies confirmed caffeine mouth rinsing benefits for exercise performance, but none have focused on muscular performance so far.
So, a multidisciplinary team of scientists from Turkey, Spain, Iran, and Brazil, aimed to assess the effects of different dosages of caffeine mouth rinse on physical performance in male athletes.
This study investigated the effects of caffeine mouth rinsing on both strength and muscular endurance by assessing bench press (one repetition maximum and 60% of repetitions to failure) in resistance-trained men aged 21–25 with BMI of 17 ± 2 kg/m2.
The respondents rinsed their mouth with 25 ml solutions containing 1%, 2%, and 3% caffeine mouth rinse, as well as placebo.
The results showed that muscular endurance response tends to be dose-dependent. For example, five seconds of mouth rinsing with high doses (750 mg) were most effective in improving bench press endurance performance.
In conclusion, the authors speculated that these results could be implemented in resistance-trained individuals’ daily training to increase their muscular endurance performance.
The recommendations also include using 750 mg of caffeine mouth rinse during training in the early morning and avoiding caffeine ingestion, which takes up to an hour to metabolize and take action.