Performance of muscle strength and fatigue tolerance in young trained women supplemented with caffeine.
Study Goal
The researchers aimed to verify the effect of caffeine supplementation on muscular strength and fatigue tolerance in young trained women.
Results Summary
Caffeine improved tolerance to exhaustion and showed a tendency to enhance strength, particularly in Hack Squat, Bench Press, and Knee Extension Exhaustion tests. The effects were statistically significant, though some variability was observed across different exercises.
Population
Young trained women (25±5 years old, BMI 20-23 kg/m², minimum 12 months of resistance training).
Effective Dosage
6 mg/kg, administered 30 minutes before testing.
Duration
Four consecutive blocks, one week apart.
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
caffeine supplementation | increase | tolerance to exhaustion | young trained women | - | improved tolerance to exhaustion | #1 |
caffeine supplementation | increase | strength | young trained women | - | has tendency to improve strength | #2 |
caffeine supplementation | increase | performance | women engaged in sports with these physical valences | - | improved performance | #3 |
caffeine supplementation | increase | Hack Squat (HS) | young trained women | 99, 109, 108, 121*; P<0.001 | resulted in Hack Squat (HS) values | #4 |
caffeine supplementation | increase | Bench Press (BP) | young trained women | 22, 26*, 25*, 27*; P<0.05 | resulted in Bench Press (BP) values | #5 |
caffeine supplementation | increase | Knee Extension Exhaustion (DS) | young trained women | 28, 35*,**, 30*, 37**; P<0.001 | resulted in Knee Extension Exhaustion (DS) values | #6 |
caffeine supplementation | increase | delta ([C1+C2/2]-[B+P/2]) | young trained women | PD=0 (P>0.05), HS=12 (P=0.04), BP=3 (P=0.007), DS=7 (P=00.1) | resulted in delta values | #7 |
BACKGROUND: The aim of this paper was to verify the effect of caffeine supplementation on the muscular strength and fatigue tolerance of young trained women. METHODS: Eight women of 25±5-years-old, who had undergone a minimum of 12 months of continuous resisted training, Body Mass Index 20-23 kg/m2 were submitted to 4 tests: One Repetition Maximum (1-RM, kg) to pull down (PD), Hack Squat (HS), Bench Press (BP), and Knee Extension Exhaustion (drop-set, 100/80/60 kg, repetitions) (DS). They performed the tests in 4 consecutive blocks one-week apart crossover system: basal without caffeine (B); first caffeine (C1); placebo with starch supplementation (P); second caffeine (C2). Caffeine supplementation 6 mg.kg-1 30 minutes before. The paired t-test and repeated ANOVA with Tukey-Kramer were performed. RESULTS: Respectively for B, C1, P and C2 to each test were PD (52, 54, 56, 55, P>0.05); HS (99, 109, 108, 121*; P<0.001); BP (22, 26*, 25*, 27*; P<0.05); DS (28, 35*,**, 30*, 37**; P<0.001). To comparison of B, P and mean caffeine (C1+C2/2) results respectively were: HS (99, 108*, 115***; P<0.05); BP (22, 25*, 26*; P<0.05); DS (28, 30#, 36**; P<0.01 and P<0.001). The delta ([C1+C2/2]-[B+P/2]) were PD=0 (P>0.05), HS=12 (P=0.04), BP=3 (P=0.007), DS=7 (P=00.1). CONCLUSIONS: Caffeine improved tolerance to exhaustion and has tendency to improve strength in this young women. Probably caffeine supplementation is useful to improve performance in women engaged in sports with these physical valences. An investigation with a major numbers of volunteers could elucidate some controversies observed here.