Acute Effects of a Caffeine-Containing Supplement on Anaerobic Power and Subjective Measurements of Fatigue in Recreationally Active Men.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
caffeine-containing supplement | no change | average power | recreationally active men | p = 0.22 | No significant differences were observed | #1 |
caffeine-containing supplement | no change | peak power | recreationally active men | p = 0.43 | No significant differences were observed | #2 |
caffeine-containing supplement | increase | fatigue | recreationally active men | Δ = 0.93 | resulted in a significant increase | #3 |
placebo beverage | increase | fatigue | recreationally active men | Δ = 1.71 | resulted in a significant increase | #4 |
caffeine-containing supplement | decrease | perceived measures of fatigue | recreationally active men | - | improved | #5 |
caffeine-containing supplement | no change | power indices assessed through vertical jump | recreationally active men | - | did not improve | #6 |
caffeine-containing supplement | no change | power indices assessed through nonmotorized treadmill sprinting | recreationally active men | - | did not improve | #7 |
caffeine beverage | decrease | perceived fatigue during acute anaerobic exercise | - | - | may be beneficial for reducing | #8 |
Hahn, CJ, Jagim, AR, Camic, CL, and Andre, MJ. Acute effects of a caffeine-containing supplement on anaerobic power and subjective measurements of fatigue in recreationally active men. J Strength Cond Res 32(4): 1029-1035, 2018-Studies show mixed results for the effects of caffeine on performance, warranting further investigation. The purpose of this study was to examine the acute effects of a caffeine-containing supplement on anaerobic power and subjective measurements of fatigue during resisted sprinting on men. Fourteen recreationally active men (N = 14; [mean ± SD], age: 21.0 ± 0.7 years, height: 178.5 ± 5.1 cm, body mass: 77.3 ± 9.6 kg, and percent body fat: 12.6 ± 4.8%) participated in a double-blind, placebo-controlled, within-subject crossover design study. The first visit required each participant to complete 3 sets of practice sprints on a nonmotorized treadmill ranging from 10 to 20 seconds. During the second visit, participants completed 5 more practice sprints ranging from 15 to 25 seconds. During the third and fourth visits, participants ingested one serving of a caffeine-containing or placebo beverage (the opposite beverage was consumed during the fourth visit), rested for 20 minutes, and completed a dynamic warm-up before sprinting. Anaerobic power was assessed using a countermovement vertical jump and nonmotorized treadmill sprint test. Psychological variables were scored using a 5-point Likert scale. No significant (p ≤ 0.05) differences were observed between conditions for average (p = 0.22) or peak power (p = 0.43). Both conditions resulted in a significant increase in fatigue, although the increase was less for the caffeine condition (caffeine [INCREMENT] = 0.93 and placebo [INCREMENT] = 1.71). These findings indicated that the caffeine-containing supplement improved perceived measures of fatigue but not power indices assessed through vertical jump or nonmotorized treadmill sprinting. The consumption of a caffeine beverage may be beneficial for reducing perceived fatigue during acute anaerobic exercise, particularly when repeated sprints are used.