Caffeinated chewing gum improves the batting and pitching performance of female softball players: a randomized crossover study.

BACKGROUND

The purpose of this study was to investigate the effects of caffeinated chewing gum on female softball pitching and hitting performance in trained female softball fielders and pitchers.

METHODS

Twenty-four trained female softball players (10 pitchers and 14 fielders) were divided into a caffeine chewing gum trial (CAF) or a placebo trial (PLA) in a single-blind, randomized, crossover experimental design. Two pieces of gum containing 100 mg of caffeine (CAF) or without caffeine (PLA) were chewed for 10 minutes and then spit out, followed by a 15-minute warm-up. The physical tests included grip strength and countermovement jump (CMJ). The softball-specific tests included pitching or hitting. The two trials were separated by seven days.

RESULTS

The CAF trial had significantly higher grip strength than the PAL trial in fielder (P=0.032, Cohen's d=0.29) and pitcher (P=0.016, Cohen's d=0.33). The height of CMJ in fielders was significantly higher in the CAF trial than in the PLA trial (P=0.015, Cohen's d=0.65) but not in pitchers (P=0.596, Cohen's d=0.15). The fielder's average and maximum batting exit speeds were significantly higher in the CAF trial than in the PLA trial (P<0.05). The average and max fastball speeds of the CAF trial were significantly higher than that of the PLA trial in pitchers (P<0.05).

CONCLUSIONS

The study showed that chewing gum containing two pieces of gum containing 100 mg of caffeine effectively improved female softball fielder's batting performance and pitcher's pitching performance.