The Effect of Caffeine on the Velocity of Half-Squat Exercise during the Menstrual Cycle: A Randomized Controlled Trial
Identificadores
URI: http://hdl.handle.net/20.500.12020/1138ISSN: 2072-6643
DOI: https://doi.org/10.3390/nu11112662
Fecha
2019Tipo de documento
articleÁrea/s de conocimiento
Ciencias de la Actividad Física y del DeporteMateria/s Unesco
2411.06 Fisiología del EjercicioResumen
Recent literature confirms the ergogenic effect of acute caffeine intake to increase muscle
strength and power in men. However, the information about the effect of caffeine on muscle
performance in women is uncertain and it is unknown whether its ergogenicity is similar during
the menstrual cycle. The goal of this investigation was to assess the effect of acute caffeine intake on
mean and peak velocity of half-squat exercise during three different phases of the menstrual cycle.
Thirteen trained eumenorrheic athletes (age = 31 ± 6 years; body mass = 58.6 ± 7.8 kg) participated
in a double-blind, crossover and randomized experimental trial. In the early follicular (EFP), late
follicular (LFP) and mid luteal phases (MLP), participants either ingested a placebo (cellulose) or 3
mg/kg/bm of caffeine in an opaque and unidentifiable capsule. In each trial, participants performed
a half-squat exercise at maximal velocity with loads equivalent to 20%, 40% 60% and 80% of one
repetition maximum (1RM). In each load, mean and peak velocity were measured during the
concentric phase of the exercise using a rotatory encoder. In comparison to the placebo, a two-way
ANOVA showed that the ingestion of 3 mg/kg/bm of caffeine increased mean velocity at 60% 1RM
in EFP (Δ = 1.4 ± 2.7%, p = 0.04; ES: 0.2 ± 0.2) and LFP (Δ = 5.0 ± 10.4%, p = 0.04; ES: 0.3 ± 0.4). No other
statistical differences were found for the caffeine-placebo comparison for mean velocity, but caffeine
induced an ergogenic effect of small magnitude in all of the menstrual cycle phases. These results
suggest that the acute intake of 3 mg/kg/bm of caffeine induces a small effect to increase movement
velocity during resistance exercise in eumenorrheic female athletes. The positive effect of caffeine
was of similar magnitude in all the three phases of the menstrual cycle.