González-Hernández, JM, García-Ramos, A, Castaño-Zambudio, A, Capelo-Ramírez, F, Marquez, G, Boullosa, D, and Jiménez-Reyes, P. Mechanical, metabolic, and perceptual acute responses to different set configurations in full squat. J Strength Cond Res 34(6): 1581–1590, 2020—This study aimed to compare mechanical, metabolic, and perceptual responses between 2 traditional (TR) and 4 cluster (CL) set configurations. In a counterbalanced randomized order, 11 men were tested with the following protocols in separate sessions (sets × repetitions [interrepetition rest]): TR1: 3 × 10 [0 seconds]; TR2: 6 × 5 [0 seconds]; CL1: 3 × 10 [10 seconds]; CL2: 3 × 10 [15 seconds]; CL3: 3 × 10 [30 seconds]; CL4: 1 × 30 [15 seconds]. The exercise (full squat), number of repetitions (30), interset rest (5 minutes), and resistance applied (10 repetition maximum) was the same for all set configurations. Mechanical fatigue was quantified by measuring the mean propulsive velocity during each repetition and the change in countermovement jump height observed after each set and after the whole training session. Metabolic and perceptual fatigue were assessed via the blood lactate concentration and the OMNI perceived exertion scale measured after each training set, respectively. The mechanical, metabolic, and perceptual measures of fatigue were always significantly higher for the TR1 set configuration. The 2 set configurations that most minimized the mechanical measures of fatigue were CL2 and CL3. Perceived fatigue did not differ between the TR2, CL1, CL2, and CL3 set configurations. The lowest lactate concentration was observed in the CL3 set configuration. Therefore, both the CL2 and CL3 set configurations can be recommended because they maximize mechanical performance. However, the CL2 set configuration presents 2 main advantages with respect to CL3 (a): it reduces training session duration, and (b) it promotes higher metabolic stress, which, to some extent, may be beneficial for inducing muscle strength and hypertrophy gains.

Uric acid (UA) is the most abundant antioxidant compound in saliva and one of the most sensitive biomarkers for detecting changes in the oxidative status of the organism. The aim of this study was to evaluate the effect of: (i) different methods of saliva sampling and (ii) the correction by salivary flow or total protein on UA concentrations in saliva. Paired saliva (collected by two different methods, passive drooling and using Salivette cotton rolls) and serum samples were obtained from 12 healthy men after the performance of two resistance training exercises of different level of effort that can produce different concentrations in UA in saliva. There were no significant differences between values of uric acid in saliva using Salivette and passive drool. Correlations between UA in serum and saliva and increases in UA in saliva after exercise were detected when saliva samples were obtained by passive drool and Salivette and were not corrected by salivary flow or total protein concentration. Therefore for UA measurements in saliva it would not be recommended to normalize the results by salivary flow or protein concentration. This study highlights the importance of choosing an adequate sampling method selection as well as the expression of results when analytes are measured in saliva.

Objectives: Neuromuscular re-education has focused on improving motor activities in patients with pathologies by retraining the nervous system. However, this has not yet been investigated in healthy individuals. Voluntary isometric contractions at maximal muscle shortening (VICAMS) is a new technique with the same objective. This study aimed to investigate the chronic effects of these techniques on range of motion, strength, and vertical jump. Sixty healthy, recreationally active participants (mean age: 46.4 ± 5.5), were randomly assigned to three groups (VICAMS, ballistic stretching, and control) who were trained for eight weeks. To assess chronic effects, active range of motion, maximal isometric strength, and countermovement jump height were determined before and after the intervention. Main effects of time and time∗group interactions were found for all variables (p < 0.001). Between-group differences were observed in the VICAMS group after the intervention, with significantly higher flexibility and strength values compared to the other groups. Intra-group differences were observed in the VICAMS and ballistic groups, as the values for all variables increased from baseline. In the VICAMS group, increases were observed in both flexibility (19.15 %) and strength (47.63 %). Increases in flexibility (2.59 %) and strength (1.84 %) were also observed in the ballistic group. For jumping, intra-group differences showed that both the VICAMS (16.56 %) and ballistic (4.34 %) groups had improved values compared to baseline values. Our findings suggest that VICAMS is an effective, simple, and inexpensive alternative to conventional training methods for improving flexibility and strength in rehabilitation.