Background: Although the scientific literature has previously described the impact of worksite programs based on physical activity (WPPAs) on employees’ productivity and health in different contexts, the effect of these programs has not been analyzed based on the characteristics or modalities of physical activity (PA) performed (e.g., aerobic exercise, strength training, flexibility). In addition, studies on WPPAs usually report health and productivity outcomes separately, not integrated into a single study. Knowing the health and economic-related impacts of a WPPAs could provide useful information for stakeholders and policy development.Objective: The purpose of this review was as follows: (1) to analyze the effect of different modalities of WPPAs on employees’ productivity and health and (2) to investigate the economic impact of WPPAs.Methods: This systematic review is registered in PROSPERO (CRD42021230626) and complies with PRISMA guidelines. Only randomized controlled trials from 1997 to March 2021 were included. Two reviewers independently screened abstracts and full texts for study eligibility, extracted the data, and performed a quality assessment using the Cochrane Collaboration Risk-of-Bias Tool for randomized trials. Population, instruments, comparison, and outcome (PICO) elements were used to define eligibility criteria. Eight-hundred sixty relevant studies were found through electronic searches in PubMed, Web of Science, Medline, Scopus, and SPORTDiscus databases. Once the eligibility criteria were applied, a total of 16 papers were included.Results: Workability was the productivity variable most positively impacted by WPPAs. Cardiorespiratory fitness, muscle strength, and musculoskeletal symptoms health variables improved in all the studies included. It was not possible to fully examine the effectiveness of each exercise modality because of the heterogeneity in methodology, duration, and working population. Finally, cost-effectiveness could not be analyzed because this information was not reported in most studies.Conclusion: All types of WPPAs analyzed improved workers’ productivity and health. However, the heterogeneity of WPPAs does not allow to identify which modality is more effective.

This study aimed to determine the relationship of body mass index (BMI), muscle-to-fat ratio (MFR), and handgrip strength-to-BMI ratio to physical fitness parameters in an active young population according to sex across four different time points. A total of 2256 Spanish children and adolescents (aged 5–18) from rural areas participating in an extracurricular sport in different municipal sports schools participated in this study. Participants were divided into children (5–10 years) and adolescents (11–18 years), boys and girls, and across four different time points (2018, 2019, 2020, 2021). Data on anthropometric measures (BMI, MFR, appendicular skeletal muscle mass) and physical fitness (handgrip strength, cardiorespiratory fitness, and vertical jump) were collected. Boys who were overweight, but especially boys with obesity, had higher absolute handgrip strength in children and adolescents than their normal weight counterparts in 2020 and 2021. Boys and girls with normal weight presented higher cardiorespiratory fitness and vertical jump than their overweight and obese peers over the years. The MFR was directly correlated with the cardiorespiratory fitness and vertical jump variables, but not with handgrip strength, in boys and girls. The handgrip strength-to-BMI ratio in both sexes was positively correlated to the different physical fitness parameters.  Conclusion: BMI, MFR, and handgrip strength-to-BMI can be used as health and physical fitness indicators in this population. What is Known:• BMI is the main indicator commonly used as a proxy for obesity for many years. Nevertheless, it cannot differentiate between fat mass and fat-free mass.• There are other indicators such as MFR and handgrip strength-to-BMI that might be more accurate and can serve to monitor the health and fitness of children and adolescents. What is New:• MFR showed a positive and significant correlation with cardiorespiratory fitness and vertical jump in both sexes. On the other hand, the handgrip strength-to-BMI presented a positive correlation with cardiorespiratory fitness, vertical jump, and handgrip strength.• The use of these indicators obtained through different parameters of body composition and physical fitness can serve as a tool to identify the relationships of the paediatric population with physical fitness.

The aim of this study was to evaluate the effect of a repeated sprint ability (RSA) test on the contractile properties of the muscles in elite futsal players. A total of 20 elite players completed the RSA test (7 × 30 m), and the contractile response from the rectus femoris (RF) and biceps femoris (BF) of both legs were analysed pre and post through tensiomyography. There was a significant increment in 30-m times from the third sprint onwards (p < 0.05). The percent decrement in sprint ability (RSA_DEC) with respect to the first sprint was significantly higher in the last sprint. The players did not show evidence of lateral asymmetry in any of the muscle groups analysed after the RSA test (p > 0.05). Following the RSA test there was a significant reduction in the delay time (Td) in RF, a significant decrement in half-relaxation time (Tr) in the RF, and a significant reduction in sustain time (Ts) in the RF and BF of both legs. The maximum radial displacement of the muscle belly (Dm) increased (1.6 mm; effect size = 0.75; p < 0.05) in the RF after the RSA test, indicating reduced muscle stiffness and the ability to generate strength rapidly. The decrement in performance during the RSA test was significantly correlated with changes in contraction time (Tc) in RF and BF, Td in BF, and Dm in RF (p < 0.05). The RSA test generated alterations in the contractile properties of the RF and BF in elite players. However, futsal players did not present asymmetries in any muscular parameters. The baseline contractile muscle parameters could be an important factor related to performance of players during repeated high-intensity actions.

The mechanical properties of the surfaces used for exercising can affect sports performance and injury risk. However, the mechanical properties of treadmill surfaces remain largely unknown. The aim of this study was, therefore, to assess the shock absorption (SA), vertical deformation (VD) and energy restitution (ER) of different treadmill models and to compare them with those of other sport surfaces. A total of 77 treadmills, 30 artificial turf pitches and 30 athletics tracks were assessed using an advanced artificial athlete device. Differences in the mechanical properties between the surfaces and treadmill models were evaluated using a repeated-measures ANOVA. The treadmills were found to exhibit the highest SA of all the surfaces (64.2 ± 2; p < 0.01; effect size (ES) = 0.96), while their VD (7.6 ± 1.3; p < 0.01; ES = 0.87) and ER (45 ± 11; p < 0.01; ES = 0.51) were between the VDs of the artificial turf and track. The SA (p < 0.01; ES = 0.69), VD (p < 0.01; ES = 0.90) and ER (p < 0.01; ES = 0.89) were also shown to differ between treadmill models. The differences between the treadmills commonly used in fitness centers were much lower than differences between the treadmills and track surfaces, but they were sometimes larger than the differences with artificial turf. The treadmills used in clinical practice and research were shown to exhibit widely varying mechanical properties. The results of this study demonstrate that the mechanical properties (SA, VD and ER) of treadmill surfaces differ significantly from those of overground sport surfaces such as artificial turf and athletics track surfaces but also asphalt or concrete. These different mechanical properties of treadmills may affect treadmill running performance, injury risk and the generalizability of research performed on treadmills to overground locomotion.

The aim of this research was to evaluate the influence of game surface and pitch size on the physiological responses, jump performance and perceptions of sub-elite female soccer players playing four-a-side games. Sixteen sub-elite female soccer players were divided into four groups of four...

This study aimed to analyze the associations of maturity status, chronological age and sex with physical fitness and body composition among active children. A total of 1682 children (72% boys; age = 11.22 ± 2.64 years; height = 147.57 ± 15.87 cm; weight = 44.55 ± 15.29 kg) from rural areas participating in extracurricular sports were divided into four groups according to their sex and maturity status (prepubertal and pubertal according to stages described by Tanner). Body composition (body mass index, muscle mass and fat mass) and physical fitness (20-m shuttle-run test, handgrip strength and vertical jump) were assessed using standardized procedures. A two-way ANOVA and product–moment correlations were performed. Prepubertal boys had more fat mass (%) than pubertal boys [P<0.001; effect size (ES): 0.45], while prepubertal girls had more muscle mass (%) than pubertal girls (P<0.001; ES: 0.47). The pubertal group displayed higher fitness outcomes (absolute values) regardless of sex (P<0.05). However, the prepubertal group had higher percentile values in the 20-m shuttle-run test and vertical jumps than the pubertal group regardless of sex (P < 0.001; ES: 0.29–0.48). All the measures of physical fitness were positively associated with chronological age and muscle mass (%). Although absolute values of body composition and physical fitness appear to increase among pubertal children participating in extracurricular sports, the percentiles indicate that puberty is accompanied with a loss of a physical fitness levels. Thus, extracurricular sports might not be enough to enhance fitness among adolescents.