Effects of dual-task resistance exercise on cognition, mood, depression, functional fitness, and activities of daily living in older adults with cognitive impairment: a single-blinded, randomized controlled trial.

BACKGROUND: Regular exercise is emphasized for the improvement of functional capacity and independence of older adults. This study aimed to compare the effects of a dual-task resistance exercise program and resistance exercise on cognition, mood, depression, physical function, and activities of daily living (ADL) in older adults with cognitive impairment. METHODS: A total of 44 older adults participated in the study. Participants were randomly allocated to an experimental group (n = 22) performing a dual-task resistance exercise program for cognitive function improvement and a control group (n = 22) performing a resistance exercise program. Both groups performed the exercise for 40 min per session, three times a week, for 6 weeks (18 sessions). Cognition, mood, depression, functional fitness, and ADL were quantified before and after the intervention using the Mini-Mental State Examination (MMSE), profile of mood states (POMS), geriatric depression scale (GDS), senior fitness test (SFT), and Korean version of ADL, respectively. RESULTS: There was a significant time and group interaction on the MMSE (p = 0.044). There were no significant time and group interactions in the POMS, GDS, SFT, or ADL. Cognitive function (p < 0.001), mood (p < 0.001), depression (p < 0.001), functional fitness (p < 0.001), and ADL (p < 0.001) significantly improved after dual-task resistance exercise, and cognitive function (p < 0.001), mood (p < 0.001), depression (p < 0.001), functional fitness (p < 0.001), and ADL (p < 0.001) significantly improved after resistance exercise. CONCLUSIONS: Dual-task resistance exercise is more effective than resistance exercise in improving cognitive function in older adults with cognitive impairment. Both dual-task resistance exercise and resistance exercise improves mood, depression, functional fitness, and ADL after the intervention. We propose using dual-task resistance exercises for cognitive and physical health management in the older adults with cognitive impairment. TRIAL REGISTRATION: This study was registered with the Clinical Research Information Service (WHO International Clinical Trials Registry Platform) (Registration ID, KCT0005389; Registration date, 09/09/2020).

Activities of daily living, self-efficacy and motor skill related fitness and the interrelation in children with moderate and severe Developmental Coordination Disorder.

BACKGROUND: Children with Developmental Coordination Disorder (DCD) are diagnosed based on poor motor skills that impact their daily activities. However, this may also lead to lower predilection and participation in physical activities and a higher risk to develop health problems. OBJECTIVE: To determine motor skill related levels in children with moderate and severe DCD and compare that to typically developing children (TD). The study also aimed to determine the level of activities of daily living (ADL) as reported by their parent and self-efficacy as reported by the children. Lastly, the relation of motor skill related fitness, ADL, and self-efficacy has been examined. METHODS: A cross-sectional study has compared TD children (n = 105) and children with DCD (n = 109; 45 moderate DCD and 64 severe DCD) from elementary schools in Tunisia between 7 and 10 years of age. The DCDDaily-Questionnaire and Children's Self-perceptions of Adequacy in and Predilection for Physical Activity Questionnaire have been used to determine ADL and adequacy towards physical activity, respectively. The PERF-FIT has been used to measure motor skill related fitness levels. RESULTS: Large group differences (p = 0.001) were found for ADL and all domains of self-efficacy between TD and DCD children. However, ADL and self-efficacy were not different between moderate and severe DCD. Motor skill related fitness was significantly lower (p = 0.01) for children with DCD than TD children, and between children with moderate and severe DCD. The relation between self-efficacy and DCDDaily-Q was different in the two DCD groups. Slow motor learning was associated with lower perceived enjoyment in physical education in the moderate DCD group, and with lower perceived adequacy in physical education in the severe DCD group. CONCLUSIONS: Children with DCD participate and enjoy physical activity less than their peers. This combination of lower participation, lower predilection to physical activity and lowered motor skill-related fitness is a concern for the present and future health status of children with DCD.

Research on the effect of different aerobic activity on physical fitness and executive function in primary school students.

To evaluate the effect of 16 weeks of different aerobic activity on physical fitness and executive functions in primary school students. 90 right-handed students from China (Boys = 46; Girls = 44) participated in our study and were randomly separated into four groups: 20 in the control group (Con), 23 in the physical activity group (PA), 25 in the intellectual activity group (IA), 22 in the physical activity and intellectual activity group (PA + IA). The students in PA, IA and PA + IA group received aerobic exercise program lasted 40 min daily, 4 days a week for 16 weeks, regular physical activity in the PA group, intellectual activity in the IA group, physical activity couple with intellectual activity in the PA + IA group, respectively. All the students participate the experiment for body composition, physical fitness (cardiopulmonary fitness, muscle strength, speed sensitivity, flexibility quality), executive functions and saliva analysis test before and after 16 weeks. There was no significant effect of 16 weeks different aerobic exercise interventions on body composition before and after exercise interventions among four groups in children (p > 0.05). The results were obtained by inter-group and intra-group comparisons that different exercise interventions (physical activity, intellectual activity, physical combine with intellectual activity), all can significantly improve physical fitness parameters (cardiopulmonary fitness, muscle strength, speed sensitivity and flexibility quality), and executive functions parameters (inhibitory control, working memory, reaction time cognitive flexibility), as well as the concentration of saliva GH and IGF-I (p < 0.05) in children. Our experiment further demonstrated that the improvement effect of the two exercises together is more significant than that of the single exercise ways. Both physical and intellectual activity can effectively improve physical fitness and executive function in children, and the improvement effect of the two exercises together is more significant than that of the single exercise ways.

Brisk walking improves motor function and lower limb muscle strength in Chinese women aged 80 years and older.

This study investigates the effects of a 12-week brisk walking exercise regimen on motor function improvements in elderly women. Twenty-six elderly women, aged 84.2 ± 3.2 years, participated in a 12-week brisk walking exercise program. Fitness assessments and blood biomarker analyses (including CHO, HDLC, LDLC, TC) were conducted pre- and post-intervention. Additionally, targeted metabolomics was employed to measure short-chain fatty acids, amino acids, and vitamin metabolites. The intervention led to significant enhancements in participants' flexibility (p < 0.05), lower limb muscle strength (p < 0.01), and cardiorespiratory endurance (p < 0.01), while muscle mass showed no significant changes. Fifteen significant differential metabolites were identified (VIP > 1.0, FC > 1.2 or < 0.8, and p < 0.05), with arginine, ornithine, aspartic acid, glutamine, phenylalanine, tyrosine, and pantothenic acid playing key roles across seven metabolic pathways. A 12-week brisk walking exercise program significantly enhanced flexibility, lower limb muscle strength, and cardiorespiratory endurance among elderly women. These improvements did not extend to muscle mass or upper limb muscle strength. The observed enhancement in exercise capacity may be attributed to improved regulation of neurotransmitters.

Multimodal prehabilitation in elective oncological colorectal surgery enhances preoperative physical fitness: a single center prospective real-world data analysis.

BACKGROUND: Surgery can lead to curation in colorectal cancer (CRC) but is associated with significant morbidity. Prehabilitation plays an important role in increasing preoperative physical fitness to reduce morbidity risk; however, data from real-world practice is scarce. This study aimed to evaluate the change in preoperative physical fitness and to evaluate which patients benefit most from prehabilitation. MATERIALS AND METHODS: In this single-arm prospective cohort study, consecutive patients undergoing elective colorectal oncological surgery were offered a 3- to 4-week multimodal prehabilitation program (supervised physical exercise training, dietary consultation, protein and vitamin supplementation, smoking cessation, and psychological support). The primary outcome was the change in preoperative aerobic fitness (steep ramp test (SRT)). Secondary outcomes were the change in functional walking capacity (6-minute walk test (6MWT)), and muscle strength (one-repetition maximum (1RM) for various muscle groups). To evaluate who benefit most from prehabilitation, participants were divided in quartiles (Q1, Q2, Q3, and Q4) based on baseline performance. RESULTS: In total, 101 patients participated (51.4% male, aged 69.7 ± 12.7 years). The preoperative change in SRT was +28.3 W, +0.36 W/kg, +16.7% (P<0.001). Patients in all quartiles improved at the group level; however, the relative improvement decreased from Q1-Q2, Q2-Q3, and Q3-Q4 (P=0.049). Change in 6MWT was +37.5 m, +7.7% (P<0.001) and 1RM improved with 5.6-33.2 kg, 16.1-32.5% for the various muscle groups (P<0.001). CONCLUSION: Prehabilitation in elective oncological colorectal surgery is associated with enhanced preoperative physical fitness regardless of baseline performance. Improvements were relatively larger in less fit patients.

Clustered Cardiometabolic Risk and the "Fat but Fit Paradox" in Adolescents: Cross-Sectional Study.

The "fat but fit paradox" states that people who are fit have a lower cluster cardiometabolic risk (CCMR), even if they are overweight or obese. Therefore, the objective was to investigate the CCMR between four categories based on the "fat but fit paradox" variable, in different fitness categories-cardiorespiratory fitness, muscular fitness, and physical fitness-in adolescents. Body composition, cardiorespiratory fitness, muscle fitness, blood samples, and blood pressure were assessed in 230 adolescents, and cardiometabolic risk and three different "fat but fit paradox" variables were calculated. Participants with a higher CRF exhibited a lower CCMR within their body mass index (BMI) category (p < 0.05). Participants with a high BMI and high muscular fitness showed a lower CCMR than participants with a low muscular fitness and a similar BMI, or low BMI and low muscular fitness (p < 0.05). When both variables, CRF and muscular fitness, were combined, their effectabove CCMR increased (p < 0.05). Across all fitness categories, the fat and unfit group, whether considered individually or combined, exhibited the highest risk of CCMR (p < 0.05). This study confirms the "fat but fit paradox" in different physical fitness categories, showing the importance of both CRF and muscular fitness as predictors of CCMR, with the combination of both variables showing a greater agreement.

Exploring the Impact of Firefighter Trainee Fitness on Academy Graduation or Release.

ABSTRACT: Lockie, RG, Orr, RM, Montes, F, and Dawes, JJ. A research note exploring the impact of firefighter trainee fitness on academy graduation or release. J Strength Cond Res 38(5): 999-1003, 2024-This study investigated the impact of fitness test performance on firefighter trainee ability to graduate an academy using ordinal logistic generalized linear models. Retrospective analysis was conducted on trainee data ( N = 686) from one fire department who completed an occupational physical ability test (OPAT) that included the following: Illinois agility test (IAT); push-ups; pull-ups; leg tucks; maximal aerobic capacity (V̇ o2 max); backward overhead 4.54-kg medicine ball throw (BOMBT); 10-repetition maximum deadlift; and 91.44-m farmer's carry. Data were recorded in raw and scaled scores based on internal scoring (tests scored from 0 to 100; maximum total OPAT score of 800). Trainees were split into graduated ( n = 576) or released ( n = 110) groups. Data were analyzed through ordinal logistic generalized linear models ( p < 0.05). Raw and scaled scores were investigated separately, with odds ratios (OR) and confidence intervals (CI) produced. Regarding raw scores, there was a difference in the odds of graduating relative to the IAT (OR = 1.357; CI = 1.047-1.760; p = 0.021), BOMBT (OR = 0.744; CI = 0.628-0.882; p < 0.001), and V̇ o2 max (OR = 0.907; CI = 0.862-0.954; p < 0.001). For scaled scores, there was a difference in the odds of graduating relative to the points attained for the BOMBT (OR = 0.985; CI = 0.972-0.999; p = 0.032), deadlift (OR = 0.982; CI = 0.968-0.995; p = 0.008), and total OPAT (OR = 0.994; CI = 0.988-1.000; p = 0.047). Change-of-direction speed (IAT), total-body power (BOMBT), aerobic fitness (V̇ o2 max), lower-body strength (deadlift), and overall fitness (total OPAT points) impacted the odds of trainee fire academy graduation. The IAT presented as the largest impacting variable where, for every unit increase in time (i.e., a slower IAT), there was 1.36 greater chance of a trainee being released from the academy.

Physical fitness in children with Marfan and Loeys-Dietz syndrome: associations between cardiovascular parameters, systemic manifestations, fatigue, and pain.

Children with Marfan (MFS) and Loeys-Dietz syndrome (LDS) report limitations in physical activities, sports, school, leisure, and work participation in daily life. This observational, cross-sectional, multicenter study explores associations between physical fitness and cardiovascular parameters, systemic manifestations, fatigue, and pain in children with MFS and LDS. Forty-two participants, aged 6-18 years (mean (SD) 11.5(3.7)), diagnosed with MFS (n = 36) or LDS (n = 6), were enrolled. Physical fitness was evaluated using the Fitkids Treadmill Test's time to exhaustion (TTE) outcome measure. Cardiovascular parameters (e.g., echocardiographic parameters, aortic surgery, cardiovascular medication) and systemic manifestations (systemic score of the revised Ghent criteria) were collected. Pain was obtained by visual analog scale. Fatigue was evaluated by PROMIS® Fatigue-10a-Pediatric-v2.0-short-form and PROMIS® Fatigue-10a-Parent-Proxy-v2.0-short-form. Multivariate linear regression analyses explored associations between physical fitness (dependent variable) and independent variables that emerged from the univariate linear regression analyses (criterion p < .05). The total group (MFS and LDS) and the MFS subgroup scored below norms on physical fitness TTE Z-score (mean (SD) -3.1 (2.9); -3.0 (3.0), respectively). Univariate analyses showed associations between TTE Z-score aortic surgery, fatigue, and pain (criterion p < .05). Multivariate analyses showed an association between physical fitness and pediatric self-reported fatigue that explained 48%; 49%, respectively, of TTE Z-score variance (F (1,18) = 18.6, p ≤ .001, r2 = .48; F (1,15) = 16,3, p = .01, r2 = .49, respectively).    Conclusions: Physical fitness is low in children with MFS or LDS and associated with self-reported fatigue. Our findings emphasize the potential of standardized and tailored exercise programs to improve physical fitness and reduce fatigue, ultimately enhancing the physical activity and sports, school, leisure, and work participation of children with MFS and LDS. What is Known: • Marfan and Loeys-Dietz syndrome are heritable connective tissue disorders and share cardiovascular and systemic manifestations. • Children with Marfan and Loeys-Dietz syndrome report increased levels of disability, fatigue and pain, as well as reduced levels of physical activity, overall health and health-related quality of life. What is New: • Physical fitness is low in children with Marfan and Loeys-Dietz syndrome and associated with self-reported fatigue. • Our findings emphasize the potential of standardized and tailored exercise programs to improve physical fitness and reduce fatigue, ultimately enhancing the physical activity and sports, school, leisure, and work participation of children with Marfan and Loeys-Dietz syndrome.

Could BIA-derived phase angle predict health-related musculoskeletal fitness? A cross-sectional study in young adults.

OBJECTIVES: To our knowledge, little evidence exists on the relationships between body composition and health-related physical fitness; in particular, musculoskeletal fitness. Bioimpedance index phase angle (bioelectrical impedance analysis raw variables) is a candidate predictor of health-related fitness, a marker of fat-free and body cell mass, respectively. The aim of this study was to evaluate body composition, raw bioelectrical impedance analysis variables, and health-related fitness in young adults and investigate their mutual relationships to identify predictors of muscle strength. METHODS: The study included 229 young adults (115 men and 114 women; 24.2 ± 3 y; body mass index 19-30 kg/m²). Anthropometry was measured with standardized procedures. Whole-body BIA (50 kHz) was performed for impedance and phase angle. Predictive equations estimated fat-free mass and percentage body fat. The bioimpedance index was calculated as stature²/impedance. Musculoskeletal fitness was assessed by handgrip strength, standing broad jump, squat jump, and countermovement jump. RESULTS: In both sexes, health-related fitness had stronger associations with body composition than stature or weight. Handgrip strength was related to fat-free mass and bioimpedance index, while an inverse association with percent body fat emerged for standing broad jump, squat jump and countermovement jump. Phase angle is directly correlated with handgrip strength, standing broad jump, squat jump, and countermovement jump. In multiple regression analysis phase angle was an independent predictor of all health-related fitness tests, along with fat-free mass (or bioimpedance index) for handgrip strength, and with sex and percent body fat for the three jump tests. CONCLUSIONS: The present study provided consistent information on the relationships between body composition and health-related fitness in young adults. Phase angle emerged as a significant predictor of all health-related fitness measures and might be useful for a more consistent assessment of musculoskeletal fitness.

Characterising the physical demands of critical tasks across the Royal Australian Air Force.

BACKGROUND: Militaries have historically utilised generic physical fitness tests to assess physical readiness, but there has been a recent shift to develop physical employment standards (PES) based on actual job demands. OBJECTIVE: The purpose of this investigation was to characterise the physical demands of critical tasks performed by Royal Australian Air Force (RAAF) personnel to inform PES development. METHODS: Job task analysis were performed for 27 RAAF trades. Criterion tasks were identified through a systematic approach involving workshops and field-observations. The identified tasks were assessed for dominant physical capacity and grouped into movement-based clusters. Psychophysiological measures were collected from personnel performing the tasks. RESULTS: Of 87 criterion tasks, 92% were characterised as manual handling dominant. Across these 87 tasks the principal physical capacities were: muscular strength (59%), muscular endurance (52%) and cardiorespiratory endurance (39%). The most common movement clusters were Lift to Platform (44%) and Lift and Carry (38%). Lift to Platform tasks required lifting to a median height of 1.32 m (1.20 -1.65 m) and a median mass of 25.0 kg (21.0 -28.9 kg) per person. Median carry mass was 25.0 kg (22.4 -36.1 kg) per person and distance was 26.0 m (17.5 -50.0 m). Median task mean 'Vdot;O2, HR and RPE were 1.8 L.min- 1 (1.5-2.2 L.min- 1), 137 b.min- 1 (120-144) and 13 (12-14). CONCLUSIONS: The high proportion of manual handling criterion tasks emphasises the importance of these activities and the underlying physical capacities for RAAF personnel. Current fitness assessments are unlikely to predict job task performance.

Effects of Plyometric Training on Physical Fitness Attributes in Handball Players: A Systematic Review and Meta-Analysis.

This meta-analysis aimed to examine the effects of plyometric training on physical fitness attributes in handball players. A systematic literature search across PubMed, SCOPUS, SPORTDiscus, and Web of Science identified 20 studies with 563 players. Plyometric training showed significant medium-to-large effects on various attributes: countermovement jump with arms (ES = 1.84), countermovement jump (ES = 1.33), squat jump (ES = 1.17), and horizontal jump (ES = 0.83), ≤ 10-m linear sprint time (ES = -1.12), > 10-m linear sprint time (ES = -1.46), repeated sprint ability with change-of-direction time (ES = -1.53), agility (ES = -1.60), maximal strength (ES = 0.52), and force-velocity (muscle power) (ES = 1.13). No significant impact on balance was found. Subgroup analysis indicated more pronounced agility improvements in players ≤ 66.6 kg compared to > 66.6 kg (ES = -1.93 vs. -0.23, p = 0.014). Additionally, greater improvements were observed in linear sprint and repeat sprint ability when comparing training durations of > 8 weeks with those ≤ 8 weeks (ES = -2.30 to -2.89 vs. ES = -0.92 to -0.97). In conclusion, plyometric training effectively improves various physical fitness attributes, including jump performance, linear sprint ability, maximal strength, muscle power and agility.

Beyond change scores: Employing an improved statistical approach to analyze the impact of entry fitness on physical performance during British Army basic training in men and women.

The aim was to use a robust statistical approach to examine whether physical fitness at entry influences performance changes between men and women undertaking British Army basic training (BT). Performance of 2 km run, seated medicine ball throw (MBT) and isometric mid-thigh pull (MTP) were assessed at entry and completion of Standard Entry (SE), Junior Entry-Short (JE-Short), and Junior Entry-Long (JE-Long) training for 2350 (272 women) recruits. Performance change was analyzed with entry performance as a covariate (ANCOVA), with an additional interaction term allowing different slopes for courses and genders (p < 0.05). Overall, BT courses saw average improvements in 2 km run performance (SE: -6.8% [-0.62 min], JE-Short: -4.6% [-0.43 min], JE-Long: -7.7% [-0.70 min]; all p < 0.001) and MBT (1.0-8.8% [0.04-0.34 m]; all p < 0.05) and MTP (4.5-26.9% [6.5-28.8 kg]; all p < 0.001). Regression models indicate an expected form of "regression to the mean" whereby test performance change was negatively associated with entry fitness in each course (those with low baseline fitness exhibit larger training improvements; all interaction effects: p < 0.001, η p 2 $$ {\eta}_{\mathrm{p}}^2 $$ > 0.006), particularly for women. However, when matched for entry fitness, men displayed considerable improvements in all tests, relative to women. Training courses were effective in developing recruit physical fitness, whereby the level of improvement is, in large part, dependent on entry fitness. Factors including age, physical maturity, course length, and physical training, could also contribute to the variability in training response between genders and should be considered when analyzing and/or developing physical fitness in these cohorts for future success of military job-task performance.

Gender and Body Mass Index Difference in Aerobic Capacity: A Study in Moroccan High School Students.

Different tests are used to evaluate the aerobic capacity of a person. This study aims to investigate the gender and Body Mass Index (BMI) difference in aerobic capacity measured by using shuttle and Spartacus test. The study was conducted on 230 high school students (135 girls and 95 boys) followed their study in public establishment in kenitra city (Morocco). All participants were classified according to their gender (male vs. female) and their BMI (normal weight vs. overweight-obese) and performed the both test of shuttle and Spartacus. Running speed at the last completed stage, run time, maximum heart rate (max HR) max HR and perceived exertion were measured and analyzed. For each test, VO2max was estimated by using the proposed equation. There was significant BMI difference in the measured parameters (p<0.001). Difference in VO2max between male and female remained significant with high-speed level in boys. A significant difference between males and females (p < 0.001) was observed in shuttle test. Participants with normal weight or physical activity had good aerobic capacity. Compared to the Shuttle test, the Spartacus provides a 11.5% higher final speed (11.2 vs. 9.7km/h) and a total test time 2.3 times longer (11.3vs. 4.9 min) (p < 0.001). Our study underlines the interest of the Spartacus test and is preliminary. Indeed, these results must now be replicated in a larger sample of obese adolescents.

The joint profiles of cardiorespiratory fitness and muscle strength on daily physical activity levels in patients with symptomatic peripheral artery disease: A cross-sectional study.

INTRODUCTION: In peripheral artery disease (PAD) patients, the joint profile of low strength and cardiorespiratory fitness on movement behaviors, specifically physical activity levels and sedentary time, remains unclear. PURPOSE: To investigate the joint profiles between cardiorespiratory and neuromuscular fitness and daily physical activity among PAD patients. METHODS: Cross-sectional study in a sample of 155 PAD patients. We measured their physical activity level per week using accelerometers, assessed their muscle strength through a sit-to-stand test and cardiorespiratory fitness through a six-minute walk test. Patients were categorized into three groups: those with high strength and cardiorespiratory fitness (NC, n = 28), those with at least one component classified as low (1C, n = 88), and those with both components classified as low fitness (2C, n = 39). RESULTS: The patients in the 1C and 2C groups spent less time engaged in low-light and moderate activities compared to the NC group (low-light: NC: 2291 ± 680 minutes/week vs. 1C: 1826 ± 649 minutes/week vs. 2C: 1885 ± 651 minutes/week, p = .005; moderate: NC: 2617 ± 796 minutes/week vs. 1C: 2071 ± 767 minutes/week vs. 2C: 2092 ± 776 minutes/week, p = .005) and the patients in the 2C group spent less time engaged in vigorous activities compared to the NC and 1C groups (NC: 155 ± 148 minutes/week vs. 1C: 110 ± 110 minutes/week vs. 2C: 64 ± 70 minutes/week, p = .003). CONCLUSION: PAD patients with low strength and/or cardiorespiratory fitness are more likely to spend less time engaging in low-light and moderate physical activities and patients with low fitness in both components are more likely to spend less time engaging in vigorous physical activity.

Lower-body muscular power predicts performance on urban combat simulation.

BACKGROUND: Military operations in urban environments requires faster movements and therefore may place greater demands on soldier strength and anaerobic ability. OBJECTIVE: The aim was to study how physical fitness and body composition are associated with occupational test for urban combat soldiers before and after a 5-day military field exercise (MFE). METHODS: Twenty-six conscripts (age = 20±1 yrs.) volunteered, of which thirteen completed the study. Occupational performance was determined by using the newly developed Urban Combat Simulation test (UCS); which included 50-m sprinting, moving a truck tire (56 kg) 2 meters with a sledgehammer, a 12-m kettlebell carry (2×20 kg) up the stairs with a 3-m ascent, 4-time sandbag lifts (20 kg) with obstacle crossing, and a 20-m mannequin (85 kg) drag. Aerobic and muscle fitness, as well as anaerobic capacity were measured, and, body composition was assessed with multifrequency bioimpedance analysis. RESULTS: The UCS performance correlated significantly with standing long jump performance, as well as lower and upper body maximal strength before (r = -0.56 to -0.66) and after (r = -0.59 to -0.68) MFE, and, with body mass and FFM before (r = -0.81 to -0.83) and after (r = -0.86 to -0.91) MFE. In the regression analyses, fat free mass (R2 = 0.50, p = 0.01) and counter movement jump in combat load (R2 = 0.46, p = 0.009) most strongly explained the UCS performance. CONCLUSION: This study demonstrated that muscle mass and lower body explosive force production together with maximal strength are key fitness components related to typical urban combat soldiers' military tasks. Physical training developing these components are recommended.

Predicting Soccer Players' Fitness Status Through a Machine-Learning Approach.

PURPOSE: The study had 3 purposes: (1) to develop an index using machine-learning techniques to predict the fitness status of soccer players, (2) to explore the index's validity and its relationship with a submaximal run test (SMFT), and (3) to analyze the impact of weekly training load on the index and SMFT outcomes. METHODS: The study involved 50 players from an Italian professional soccer club. External and internal loads were collected during training sessions. Various machine-learning algorithms were assessed for their ability to predict heart-rate responses during the training drills based on external load data. The fitness index, calculated as the difference between actual and predicted heart rates, was correlated with SMFT outcomes. RESULTS: Random forest regression (mean absolute error = 3.8 [0.05]) outperformed the other machine-learning algorithms (extreme gradient boosting and linear regression). Average speed, minutes from the start of the training session, and the work:rest ratio were identified as the most important features. The fitness index displayed a very large correlation (r = .70) with SMFT outcomes, with the highest result observed during possession games and physical conditioning exercises. The study revealed that heart-rate responses from SMFT and the fitness index could diverge throughout the season, suggesting different aspects of fitness. CONCLUSIONS: This study introduces an "invisible monitoring" approach to assess soccer player fitness in the training environment. The developed fitness index, in conjunction with traditional fitness tests, provides a comprehensive understanding of player readiness. This research paves the way for practical applications in soccer, enabling personalized training adjustments and injury prevention.

Associations of lower-limb muscle strength performance with static and dynamic balance control among older adults in Taiwan.

Background: Aging is an inevitable process of life development. These physical changes can cause a decline in the functional adaptability and health status of older adult individuals. Aims: The purpose of this study was to investigate the association of lower-limb muscle strength performance with static and dynamic balance control among older adults in Taiwan. Methods: We conducted a cross-sectional study and reviewed data derived from the National Physical Fitness Survey in Taiwan 2015-2016. A total of 20,846 Taiwanese older adult individuals aged 65 years old or older were recruited as study participants. Demographic characteristics, anthropometric assessments, lifestyle habits, and health-related physical fitness measurements from this dataset were analyzed using the chi-square test, one-way analysis of variance, and linear regression analysis. Lower-limb muscle strength performance was classified into 4 groups based on quartile (Quartile 1 [Q1], Quartile 2 [Q2], Quartile 3 [Q3], and Quartile 4 [Q4]) values. Results: Increased lower-limb muscle strength levels were significantly associated with static balance in men (Q2: ß = 2.539, p < 0.0001; Q3: ß = 4.590, p < 0.0001; Q4: ß = 7.700, p < 0.0001) and women (Q2: ß = 2.022, p < 0.0001; Q3: ß = 4.179, p < 0.0001; Q4: ß = 6.920, p < 0.0001) after adjusting for potential confounders. In addition, we observed that increased lower-limb muscle strength levels were significantly associated with dynamic balance in men (Q2: ß = -1.661, p < 0.0001; Q3: ß = -2.434, p < 0.0001; Q4: ß = -3.091, p < 0.0001) and women (Q2: ß = -1.660, p < 0.0001; Q3: ß = -2.548, p < 0.0001; Q4: ß = -3.196, p < 0.0001) after adjusting for potential confounders. Conclusion: Lower-limb muscle strength was the most important factor, as it was an improved method for static and dynamic balance control in both genders.

Impact of COVID-19 Pandemic Lockdown on Body Mass Index and Physical Fitness in Chinese College Students.

PURPOSE: To explore the impact of COVID-19 pandemic lockdown (CoPL) on body mass index (BMI) and physical fitness among college students. METHODS: Two one-year cohorts, one with no pandemic lockdown (NoPL) exposure and one with CoPL exposure, were included. Baseline measurements were performed in October 2018 (NoPL) and October 2019 (CoPL), and follow-up data were collected one year later. Participants were divided into "deterioration", "no-change", and "improvement" groups based on their quartile distribution of one-year differences (follow-up-baseline) for lower 25%, middle 50%, and upper 25%. Baseline-category logit regression models were used to determine the odds ratios of deterioration and improvement in BMI and physical fitness, with "no-change" used as baseline. RESULTS: A total of 2,594 and 2,525 students were included in NoPL and CoPL cohorts, respectively. CoPL was associated with higher odds for deterioration in BMI (male), explosive strength, upper-limb muscle strength, abdominal muscle strength, and cardiorespiratory fitness, but lower odds for deterioration in BMI (female) and flexibility. CoPL was associated with lower odds for improvement in BMI (male), explosive strength, lower-limb and upper-limb muscle strength, and cardiorespiratory fitness, but higher odds for improvement in BMI (female) and flexibility. DISCUSSION: Not all dimensions of health outcomes were negatively impacted by the lockdown, as deterioration in BMI in males, muscle strength, and cardiorespiratory fitness following the CoPL were more than that in the absence of the lockdown, while deterioration in BMI in females and flexibility were less than that in the absence of the lockdown.

Do you even exercise, ref? Exploring habits of Spanish basketball referees during practice and matches.

Background: Basketball referees are a vital part of the organised competition system, although they remain an "outgroup" in sport. While physical development and fitness programming are deemed necessary for basketball officiating excellence, there is a paucity of literature exploring strategies for physical fitness management in this population. Methods: This research was a nationwide cross-sectional, self-administered online survey conducted in 2021. A sample of 628 (531 males, 97 females) referees from 18 regional referee organisations in Spain provided individual responses to gather information on demographic details, level of participation in refereeing, physical fitness practices, and match-day exercise-based regimens. The data were described using summary statistics, and the associations of the assessed variables were subsequently calculated using contingency tables. Results: Our findings reveal that a large fraction of the Spanish basketball referee population focuses on aerobic (83%) and strength (73.6%) activities, while less attention is paid to speed (36.9%) and flexibility (23.2%), and agility, coordination, and balance tasks are somewhat overlooked. No significant differences were observed among the referee categories regarding weekly training days or session duration, with most training for 15-60 min per session. Elite referees were more likely to hire personal trainers and engage in strength and flexibility exercises. Sub-elite referees showed a higher tendency to perform stretching and joint mobility activities post-match, while regional referees did so less frequently. Approximately 30.7% of referees across all competitive levels engaged in re-warm-up (RW-U) activities, with stretching and joint mobility being the most prevalent. Conclusions: Spanish basketball referees participate in routine physical exercise and fitness practices, irrespective of their competition level. While warm-up activities are prevalent, some sub-elite and regional referees do not consistently perform them, and re-warm-up routines are not extensively embraced.