EFFECTS OF PERIODIC AND CONTINUOUS RESISTANCE TRAINING ON MUSCLE STRENGTH IN DETRAINED WOMEN

Does Taking a Break Matter-Adaptations in Muscle Strength and Size Between Continuous and Periodic Resistance Training

We aimed to compare the effects of periodic resistance training (RT) and continuous RT on muscle strength and size. Fifty-five healthy, untrained participants (age 32 ± 5 years) were randomized to periodic (PRT, n = 20 completed the study, 45% females) or continuous (CRT, n = 22 completed the study, 45% females) groups. PRT completed a 10-week RT, a 10-week detraining, and a second identical 10-week RT. CRT began with a 10-week non-RT, followed by a 20-week RT. RT included twice-weekly supervised whole-body RT sessions. Leg press (LP) and biceps curl (BC) one repetition maximum (1RM), countermovement jump (CMJ) height, muscle cross-sectional area (CSA) of vastus lateralis (VL), and biceps brachii (BB) using ultrasound imaging were measured twice at the beginning and every fifth week during the intervention. Both groups increased (p < 0.001) 1RM in LP and BC, CSA in VL and BB, and CMJ height with no differences between the groups. In PRT, 1RM in LP and BC, CSA in VL and BB, and CMJ height decreased during detraining (p < 0.05). During the first 5 weeks of retraining in PRT, increases in LP 1RM, and VL and BB CSA were greater than in CRT during Weeks 10-15 of their CRT (p < 0.01). PRT and CTR ended up in similar postintervention adaptations, as decreased muscle strength and size during detraining in PRT regained rapidly during retraining. Our results therefore suggest that trainees should not be too concerned about occasional short-term training breaks in their daily lives when it comes to lifelong strength training. Trial Registration: ClinicalTrials.gov identifier: NCT05553769.

Influence of Adding Single-Joint Exercise to a Multijoint Resistance Training Program in Untrained Young Women

Barbalho, M, Gentil, P, Raiol, R, Fisher, J, Steele, J, and Coswig, V. Influence of adding single-joint exercise to a multijoint resistance training program in untrained young women. J Strength Cond Res 34(8): 2214-2219, 2020-The aim of the present study was to investigate the effects of adding single-joint (SJ) exercises to a multijoint (MJ) resistance training (RT) program on muscle strength and anthropometric measures of young women. Twenty untrained women were divided into a group that performed only MJ exercises or a group that performed both SJ and MJ exercises (MJ + SJ). Before and after 8 weeks of training, the participants were tested for 10 repetition maximum (10RM). Flexed arm circumference and triceps and biceps skinfold thickness were also measured. Both groups significantly decreased biceps (-3.60% for MJ and -3.55% for MJ + SJ) and triceps skinfold (-3.05% for MJ and -2.98% for MJ + SJ), with no significant difference between them. Flexed arm circumference significantly increased in both groups; however, increases in MJ + SJ (4.39%) were significantly greater than MJ (3.50%). Increases in 10RM load in elbow extension (28.2% for MJ and 28.0% for MJ + SJ), elbow flexion (29.8% for MJ and 28.7% for MJ + SJ), and knee extension (26.92% for MJ and 23.86% for MJ + SJ) were all significant and not different between groups. The results showed that adding SJ exercises to an MJ RT program resulted in no additional benefits in muscle performance, whilst differences in flexed arm circumference were small, but significant, in untrained women.

ISOKINETIC RESPONSE, VISCOSUPPLEMENTATION AND STRENGTH TRAINING IN GONARTHROSIS

ABSTRACT Introduction Viscosupplementation and strength training are proposed interventions in the treatment of knee osteoarthritis. Objective To describe the isokinetic response in women with knee osteoarthritis who underwent both interventions. Methods A double-blind, randomized clinical trial involving thirty women diagnosed with grade II and III bilateral knee osteoarthritis using the radiological criteria of Kellgren & Lawrence. The subjects were randomized into three groups of ten patients each: one group was submitted to viscosupplementation and strength training (VST), another was submitted to strength training (ST) only, and a third to viscosupplementation (VS) only. All evaluations followed the study phases defined as pre-procedure (PRE); after 48 hours of VS (POS-VS); after 12 weeks of training (POS T); and after eight weeks of detraining (POS D). Intra-articular knee infiltrations were performed with a single dose of Hylan GF-20 and isokinetic dynamometry to determine the maximum torque in knee extension and flexion. Pain was measured by the visual analogue scale (VAS). Results The interventions promoted improvements in the isokinetic response in all three groups and in both muscle groups, with advantage for the extensor group. A significant difference was noticed in the isokinetic response of the trained groups when compared only to the viscosupplemented group (p<0.005), and the VST group showed better isokinetic response compared to the ST group. Conclusion Combined treatment with viscosupplementation and strength training, and treatment with strength training only, presented better results in terms of isokinetic response and pain reduction than viscosupplementation alone. Level of evidence I; Therapeutic studies-Investigating the results of treatment.

Global Training Effects of Trained and Untrained Muscles With Youth Can be Maintained During 4 Weeks of Detraining

Chaouachi, A, Ben Othman, A, Makhlouf, I, Young, JD, Granacher, U, and Behm, DG. Global training effects of trained and untrained muscles with youth can be maintained during 4 weeks of detraining. J Strength Cond Res 33(10): 2788-2800, 2019-Global (whole-body) effects of resistance training (i.e., cross-education) may be pervasive with children. Detraining induces less substantial deficits with children than adults. It was the objective of this study to investigate the global responses to 4 weeks of detraining after 8 weeks of unilateral leg press (LP) training in 10-13-year-old, pre-peak-height-velocity stage boys. Subjects were randomly separated into 2 unilateral resistance training groups (high load/low repetitions [HL-LR] and low load/high repetitions [LL-HR], and control group). Assessments at pre-training, post-training, and detraining included dominant and nondominant limbs, unilateral, 1 repetition maximum (1RM) and 60% 1RM LP, knee extension, knee flexion, elbow flexion, and handgrip maximal voluntary isometric contraction (MVIC), and countermovement jump (CMJ). All measures significantly increased from pre-test to detraining for both training programs, except for elbow flexion MVIC with increases only with HL-LR. All measures except CMJ and handgrip MVIC significantly decreased from post-test to detraining, except for elbow flexion MVIC with decreases only with HL-LR. The dominant trained limb experienced significantly greater LP improvements (pre- to detraining) and decrements (post- to detraining) with LP 1RM and 60% 1RM LP. In conclusion, youth HL-LR and LL-HR global training effects of trained and untrained limbs demonstrate similar benefits (pre- to detraining) and decrements (post- to detraining) with detraining. The findings emphasize that training any muscle group in a child can have positive global implications for improved strength and power that can persist over baseline measures for at least a month.