The Benefits of Resistance Training in Obese Adolescents: A Systematic Review and Meta-analysis.

BACKGROUND: Physical activity is essential in acquiring healthy lifestyle behaviors in the early years of maturational development and preventing various diseases. Resistance training (RT) is fundamental for improving body composition and is increasingly recommended for obese adolescents. A systematic review and meta-analysis were performed to synthesize and analyze data on the effects of RT programs in this population, seeking to develop useful recommendations for health and sports professionals. METHODS: A search was performed using four databases (Web of Science, Scopus, PubMed, and ScienceDirect). According to specific inclusion criteria, twenty-one studies were selected to evaluate the impact of RT on body mass index (BMI), body fat, waist circumference, muscle strength, insulin sensitivity, lean mass and cardiorespiratory fitness. RESULTS: After the RT programs, the adolescents improved their muscle strength (SMD, 1.44; 95% CI: 0.76-2.12), cardiorespiratory fitness (SMD, 1.09; 95% CI: 0.15-2.04), BMI (SMD, 0.21; 95% CI: 0.07-0.35), waist circumference (SMD, 0.27; 95% CI: 0.06-0.47) and body fat (SMD, 0.20; 95% CI: 0.05-0.34). However, insulin sensitivity (SMD, 0.32; 95% CI: - 0.47 to 1.10) and lean mass (SMD, 0.12; 95% CI: - 0.06 to 0.31) did not reveal any changes. Different RT programs were used but it seems that 2-3 times/week ∼60 min/session of RT for 12 weeks should be recommended for positive changes. CONCLUSIONS: RT seems to be effective when the objective is to improve muscle strength, cardiorespiratory fitness and can be an efficient strategy to reduce obesity in adolescents by reducing body fat, waist circumference and body mass index. PROSPERO Registration number: CRD42022333411.

Benefits of aquatic exercise in adults with and without chronic disease-A systematic review with meta-analysis.

Aquatic exercise is being increasingly recommended for healthy individuals as well as people with some special health conditions. A systematic review with meta-analysis was performed to synthesize and analyze data on the effects of water-based training (WT) programs on health status and physical fitness of healthy adults and adults with diseases to develop useful recommendations for health and sports professionals. We searched three databases (PubMed, Web of Science, and Scopus) up to June 2021 for randomized trials that examined WT in adults. A total of 62 studies were included, of which 26 involved only healthy individuals and 36 focused on adults with chronic diseases. In the healthy group, the effects of WT on strength, balance, and cardiorespiratory fitness were beneficial, indicating the usefulness of performing WT for at least 12 weeks (2-3x/week, 46-65 min/session). Among adults with diseases, improvements were observed in patients with fibromyalgia (in balance and cardiorespiratory fitness), bone diseases (pain, balance, flexibility, and strength), coronary artery disease (strength and anthropometry), hypertension (quality of life), stroke (quality of life), diabetes (balance and quality of life), multiple sclerosis (quality of life and balance), and Parkinson's disease (pain, gait, cardiorespiratory fitness, and quality of life). Research is required to determine the effects of WT on patients with heart disease, especially coronary artery disease. In adults with chronic disease, benefits in physical fitness and/or other health-related measures were mainly observed after 8-16 weeks of training. WT is an effective physical activity when the intention is to enhance health and physical fitness in healthy adults and adults with chronic diseases.

Force Production and Coordination from Older Women in Water Fitness Exercises.

The aim of this study was to compare bilateral propulsive forces and coordination while exercising at static and dynamic conditions in the water. A total of 27 older women (age: 65.1 ± 6.7 years old) performed the following exercises: (i) horizontal upper-limbs adduction (HA; static condition) and (ii) rocking horse (RH; dynamic condition) through an incremental protocol with music cadences from 105 up to 150 b·min-1. The duration of each trial was set at 30 second (sec). Propulsive peak force (in Newton, N) of dominant (PFD) and nondominant (PFND) upper limbs was retrieved using hand sensors coupled to a differential pressure system. Significant differences in force production were found between static and dynamic exercises at higher cadences (120, 135, and 150 b·min-1). The static condition elicited higher bilateral propulsive forces and a more symmetric pattern. The in-water static exercise with bilateral action from the upper limbs proved to be the most appropriate strategy for older women to work strength and to reduce asymmetries.

Acute effects of low and high-volume resistance training on hemodynamic, metabolic and neuromuscular parameters in older adults.

OBJECTIVE: To analyze the acute effects of low or high-volume resistance training (RT) on hemodynamic, metabolic and neuromuscular parameters in institutionalized older adults. METHODS: Thirty-one subjects (78.9 ±â€¯7.2 years old) performed two RT protocols (low versus high-volume), separated by one-week rest. Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and blood lactate concentration ([La-]) were evaluated before and immediately after both RT protocols. The seated medicine ball throw (SMBT) was evaluated before and 5 min after both sessions, the countermovement jump (CMJ) height was evaluated before and 6 min after both RT protocols and the absolute handgrip strength (HGS) was evaluated before and 7 min after both RT protocols. RESULTS: At baseline, no significant differences between RT protocols were found in all variables. After training session, both RT protocols induced significant increases in SBP (low versus high-volume: 5.3% vs 10.7%), DBP (5.9% vs 6.8%), HR (6.8% vs 17.9%) and [La-] (86.1% vs 200.0%). Moreover, the high-volume protocol induced significant decreases in SMBT (-2.5%) and CMJ (-8.3%), whilst the low-volume protocol significantly increased the HGS (3.4%). CONCLUSIONS: Both RT protocols induced significant acute responses on cardiovascular and metabolic parameters, as well as on neuromuscular function in institutionalized older adults. However, a greater acute response after the high-volume RT protocol was found, thus reflecting greater hemodynamic, metabolic and neuromuscular stress than low-volume RT. Moreover, low-volume RT showed an acute increase in general strength.