de Camargo, JBB, Braz, TV, Batista, DR, Germano, MD, Brigatto, FA, and Lopes, CR. Dissociated time course of indirect markers of muscle damage recovery between single-joint and multi-joint exercises in resistance-trained men. J Strength Cond Res 36(8): 2089–2093, 2022—This study compared the time course of indirect markers of muscle damage after multi-joint and single-joint exercises. Ten resistance-trained men (years: 26.9 ± 3.0; total body mass: 83.2 ± 13.8 kg; height: 176 ± 7.0 cm; resistance training [RT] experience: 5.5 ± 2.4 years; RT frequency: 5.3 ± 0.7 sessions; relative squat 1 repetition maximum: 1.4 ± 0.3) performed, in a random order, 5 sets of 8 repetition maximum of the back squat (BS) and knee extension (KE) exercises. Rectus femoris muscle thickness (MTRF), leg circumference (LC), and muscle soreness (MS) were recorded at baseline (pre), 0, 12, 24, and 36 hours after each exercise protocol. There was a significant increase (p < 0.05) in dependent variables at every time point after both the multi-joint and single-joint exercise sessions. However, MTRF and LC were greater at 0 and 36 hours, and MS was greater at 24 and 36 hours after BS when compared with KE (all p < 0.05). This study shows that resistance-trained individuals can experience significant higher levels of indirect markers of muscle damage when performing a multi-joint lower-limb exercise compared with a single one.

No abstract

It is widely known that the aging process induces relevant impairments on both muscle morphology and function. In this sense, resistance training alongside proper protein intake are important strategies to mitigate the sarcopenia process in older individuals. However, adding protein supplementation (PS) to resistance training interventions for enhancing muscle strength and functional performance has shown mixed results in this population. Therefore, the present study aimed to review the most recent evidence regarding PS and its effects on muscle strength and functional parameters of older adults. In addition, the effect size of each individual study (post–pre intervention) was also calculated to provide further clinical relevance on the topic. The results of the studies included do not seem to support PS for healthy older adults with proper protein intake. However, further studies with other sample characteristics (very old, frail, obese, and inadequate protein consumption) must be carried out to better understand the effects of PS in an older population.

Aging is characterized by a progressive decline in function and morphological aspects of biological tissues, with especial regards to cardiovascular and musculoskeletal systems. In this sense, exercise has been shown to strongly counteract these aging-induced detrimental effects. Endurance exercise (EE) has been shown to reduce the rate of decline of factors related to cardiorespiratory fitness. In addition, the adoption of resistance training (RT) may also induce relevant adaptations, especially related to increased muscle strength and power levels, that have shown to positively influence functional aspects as improved balance and reduced risk of falls in the elderly population. Then, the aim of the present study is to briefly review the exercise literature regarding its mechanisms that could potentially present “antiaging” effects.

This study assessed associations between changes in the weekly number of sets performed and the percentage change in muscle thickness of the biceps (MTBB) and triceps (MTTB) brachii muscles. Through a retrospective analysis, sixty-eight resistance-trained subjects that participated in previous studies had their previous training volumes analyzed and compared to the volume imposed during each individual study. The relationship between variables was determined through Spearman correlation and a k-cluster analysis was performed to subdivide the participants into three groups and classified as:<0%; 0–50%, and >50% increase in the number of sets for both muscle groups. Moderate and weak correlations were observed between the alterations in training volume and changes in MTBB (rs=0.44, p=0.001) and MTTB (rs=0.35, p=0.002), respectively. A significant difference was noted between<0% to >50% for MTBB and MTTB (p=0.017; p=0.042, respectively), while no significant difference was observed between<0% to 0–50% and 0–50% to >50% (both p >0.05) for both muscle groups. In conclusion, muscle hypertrophy of the upper limbs is only weakly to moderately associated with changes in training volume of trained subjects.