Handgrip explosive force is correlated with mobility in the elderly women.

The analysis of explosive force, through rate of force development (RFD) and contractile impulse (CI), from handgrip strength data seems to be useful and promising information to study the aging of musculoskeletal system and health status. We aimed to test the hypothesis that, in elderly women, the handgrip explosive force could be better associated to the functional mobility than maximum handgrip strength. Handgrip strength and the performance of Timed Up & Go Test (TUG) were measured from sixty-five community-dwelling healthy elderly women. The average slope of the moment-time curve (Δ moment/Δ time) over the time interval of 0-200 ms relative to the onset of contraction was calculated to provide the RFD and CI. The highest strength achieved during the isometric contraction was used as maximum handgrip strength. Pearson correlations were used to assess the strength of the relationship between the handgrip strength parameters (Maximum strength and explosive force from 0-200 ms) and TUG test performance from older women. The correlation analysis showed that the TUG test performance was inversely correlated to the handgrip strength parameters, with better relationship with explosive force parameters. The handgrip explosive force seems to be a promising predictor of functional mobility of elderly women, since it showed a better relationship with functional mobility than maximum handgrip strength.

El uso de manga de compresión durante 12 horas no es suficiente para mejorar la recuperación muscular del brazo tras el daño inducido por el ejercicio / Twelve hours of a compression sleeve is not enough to improve the muscle recovery of an exercise-damaged upper arm

Objetivo: Evaluar la eficacia de la manga de compresión usada durante un período de tiempo corto (12 h) en la recuperación de los síntomas de daño muscular inducido por el ejercicio de los músculos del brazo. Métodos: En un estudio aleatorizado controlado, 13 hombres jóvenes sanos realizaron un protocolo de ejercicio estandarizado para inducir daño muscular para los flexores del codo y se dividieron inmediatamente en 2 grupos: tratados (n = 7) y control (n = 6). Se tomaron medidas de la fuerza isométrica de flexión del codo, la circunferencia del brazo (CB) y la percepción del dolor muscular antes y 24, 48, 72 y 96 h después del ejercicio, y se utilizaron como criterios de daño muscular inducido por el ejercicio. Comparaciones entre grupos se hicieron para cada variable con un ANOVA de 2 vías (2 grupos × 5 medidas) y con un nivel de significación de p < 0,05. Resultados: Se observó una reducción significativa (p < 0,001) de la fuerza muscular (∼43% y ∼34% para el grupo control y tratados, respectivamente, 24 h después del ejercicio) y un aumento significativo (p < 0,001) en la circunferencia del brazo y dolor muscular (F4,55 = 6,49 para CB y F4,55 = 6,95 para dolor muscular) a lo largo de las medidas después del ejercicio en ambos grupos, sin diferencias significativas entre ellos. Conclusiones: Nuestros resultados, junto con los hallazgos previos, sugieren que el uso de la manga de compresión durante 12 h no es suficiente para mejorar la recuperación de los síntomas de daño muscular inducido por el ejercicio de los músculos del brazo, y para lograr resultados positivos son necesarios largos períodos de compresión

Objective: To assess the efficacy of a compression sleeve worn for a short-time period (12 h) on the recovery from the symptoms of exercise-induced upper arm muscle damage. Methods: A randomized controlled study was conducted on thirteen healthy young men using a standardized and exercise-induced upper arm muscle damage protocol, and they were immediately placed into two groups: TREATED (n = 7) and CONTROL (n = 6). Isometric elbow flexion strength, upper arm circumference, and muscle soreness measurements were taken before and at 24, 48, 72 and 96 h after the damaging exercise, and were used as criteria of exercise-induced muscle damage. Group comparisons were made for each variable using a two-way ANOVA design (2 groups × 5 measurements), and with a significance level of P < .05. Results: A significant impairment (P < .001) was observed in muscle strength (∼ 43% and ∼ 34%, for CONTROL and TREATED groups, respectively, 24 h after exercise), as well as a significant increase (P < .001) in upper arm circumference (UAC) and muscle soreness (F4,55 = 6.49 for UACand F4,55 = 6.95 for muscle soreness) among the measurements after exercise for both groups, with no significant differences between them. Conclusions: These results, together with previous findings, suggest that the use of a compression garment for 12 h is not enough to improve the recovery from exercise- induced muscle damage in the upper arm, and longer periods of compression may be necessary to achieve positive outcomes

Light-emitting diode phototherapy improves muscle recovery after a damaging exercise.

The goal of the present study was to determine the effect of light-emitting diode phototherapy (LEDT) at 630 nm on muscle recovery after a damaging eccentric exercise bout. Seventeen healthy young male volunteers, without previous experience with eccentric exercise, were included in a randomized double-blinded placebo-controlled trial. They were divided into a LEDT (n = 8) and a PLACEBO group (n = 9). To induce muscle damage, subjects performed 30 eccentric contractions with a load of 100 % of maximal voluntary isometric contraction strength of the elbow flexors of the non-dominant arm. LEDT group subjects received biceps brachii phototherapy (λ 630 nm; total energy density, 20.4 J/cm2) immediately after the exercise bout. The LEDT in the placebo group was aimed at the muscle, but it remained turned off. Isometric muscle strength, muscle soreness, and elbow range of motion (ROM) were measured before and at 24, 48, 72, and 96 h the after eccentric exercise bout and compared between groups. Our results showed that the muscle soreness, muscle strength loss, and ROM impairments were significantly reduced up to 96 h after a damaging eccentric exercise bout for the LEDT group compared with the PLACEBO group. A single LEDT (630 nm) intervention immediately after a damaging eccentric exercise bout was effective in terms of attenuating the muscle soreness and muscle strength loss and ROM impairments.