Physical fitness components are bone mineral density predictors in adulthood: cross-sectional study.

BACKGROUND: Health-related physical fitness (HRPF) attributes are considered important markers beneficial to various health outcomes. However, the literature is divergent regarding HRPF and bone health in adulthood, especially due to the end of the second and beginning of the third decades of life when the peak bone mass period occurs. OBJECTIVE: To analyze which HRPF variables are areal bone mineral density (aBMD) predictors in adult males and females. METHODS: This study evaluated 137 healthy young adults aged 18-25 years (50% males). Dual-energy X-ray absorptiometry (DXA) was used to estimate fat mass and lean mass and aBMD, hand grip strength test, sit-ups test, flexibility test, lower limb muscle strength and 20-meter run were used to evaluate physical fitness. Multiple linear regression using the backward method was used to analyze bone mineral density predictors by sex. RESULTS: HRPF indicators showed correlations from R = 0.28 in the right femoral neck aBMD to R = 0.61 in the upper limbs aBMD in males; in females, correlations from R = 0.27 in total body aBMD to R = 0.68 in the lower limbs aBMD were found. In males, body mass and HRPF indicators were aBMD predictors with HRPF indicators explaining variance from R²=0.214 in the lumbar spine to R²=0.497 in the upper limbs, and in females, with the exception of the lumbar spine, variance from R²=0.237 in the right femoral neck aBMD to R²=0.442 in the lower limbs aBMD was found. CONCLUSION: Health-related physical fitness components were able to predict aBMD in different anatomical regions in young adults, especially muscle strength and cardiorespiratory fitness indicators for males, while only lean mass and fat mass for females.

Estrogen Status Influences Whole-Body Vibration Training-Induced Improvements on Muscle Mass and Strength in Female Ovariectomized Mice.

Estradiol (E2) deficiency arising from menopause is closely related to changes in body composition and declines of muscle mass and strength in elderly women. Whole-body vibration training (WBV) is an emerging approach expected to improve muscle mass and strength of older person, but the underlying mechanisms remain unclear. The balance between protein synthesis and degradation is a determining factor for muscle mass and strength, which is regulated by Akt-mTOR and FoxO1 signal pathway, respectively. In the present study, we firstly determined whether the effects of WBV on muscle mass and strength in ovariectomized female mice was affected by estrogen level, then investigated whether this was associated with Akt-mTOR and FoxO1 signal pathways. We found that (1) WBV, E2 supplementation (E) and WBV combined with E2 supplementation (WBV+E) significantly increased serum estradiol content, quadriceps muscle mass and grip strength in ovariectomized mice, accompanied with alterations of body composition (reducing fat content, increasing lean body mass and lean percent), furthermore, the altered degrees of these indicators by WBV+E were greater than WBV alone; (2) WBV, E and WBV+E remarkably increased the activities of Akt and mTOR and decreased FoxO1 activity, and the changed degrees by WBV+E were greater than WBV alone; (3) Pearson correlation coefficient revealed that serum estradiol content was positively correlated with Akt and mTOR activities, while inversely associated with FoxO1 activity. We concluded that WBV could significantly increase muscle mass and strength in ovariectomized mice, which might achieve through activating Akt-mTOR and suppressing FoxO1 signal pathways, and the improving effect of WBV on muscle mass and strength was better when in the presence of estrogen.

Effects of different levels of physical activity on arterial stiffness and physical fitness performance in firefighters.

Background: Firefighters have lower levels of physical activity while on call. It is critical to understand the impact of firefighters' physical activity on arterial stiffness. This study classified groups by physical activity level and combined peripheral vascular monitor measurement to explore the relationships between the level of physical activity and cardiovascular (CV) risk and physical fitness (PF) of firefighters, as well as the acute response to arterial stiffness (AS) following maximal aerobic exercise test (MAET) intervention. Methods: The International Physical Activity Questionnaire (IPAQ) was used to classify the participants into 3 groups: low, moderate, and high level of physical activity group, respectively. A total of 36 participants were recruited, 12 in each group. Participants were assessed for body composition, rest brachial-ankle pulse wave velocity (baPWV), handgrip strength (HGS), maximal oxygen uptake (V̇O2max), and MAET baPWV. Results: In the three groups, significant differences were observed in V̇O2max, HGS, relative fat mass (%FM), body mass index (BMI), muscle mass ratio (MMR), and Rest baPWV (p < 0.05). After maximal aerobic exercise, the MAET baPWV values decreased significantly in all groups (all p < 0.001). Rest baPWV was significantly correlated with firefighters' age, seniority, metabolic equivalents (METs), height and muscle mass (MM) (p < 0.05). Conclusions: Firefighters with high levels of physical activity had better body composition and physical fitness and lower Rest baPWV. In all three groups, baPWV was lower after the MAET than before it. Therefore, regardless of a firefighter's level of physical activity, high-intensity aerobic exercise may have a beneficial effect on arterial stiffness.

Effects of prenatal exercise interventions on maternal body composition: A secondary analysis of the FitMum randomized controlled trial.

The main objective of the study was to investigate the effects of prenatal exercise interventions on maternal body composition at 28 weeks gestation and 7-14 days after delivery. We also explored associations between physical activity (PA) per se and body composition. This study presents secondary outcomes of the FitMum randomized controlled trial, which included healthy inactive pregnant women at gestational age ≤ 15+0 weeks. They were randomized to structured supervised exercise training, motivational counselling on PA, or standard care. Maternal body composition was measured by doubly labeled water at 28 weeks gestation (n = 134) and by dual-energy X-ray absorptiometry scan 7-14 days after delivery (n = 117). PA, including moderate-to-vigorous-intensity PA (MVPA), active kilocalories, and steps, were measured continuously from inclusion to delivery by a wrist-worn activity tracker. One hundred fifty pregnant women were included with a median pre-pregnancy body mass index (BMI) of 24.1 (21.6-27.9) kg/m2. We found no differences between groups in fat mass, fat percentage or fat-free mass at 28 weeks gestation or 7-14 days after delivery. Visceral adipose tissue mass and bone mineral density measured 7-14 days after delivery did not differ between groups either. Linear regression analyses adjusted for pre-pregnancy BMI showed that a higher number of daily steps was associated with lower fat mass, fat percentage, and visceral adipose tissue mass at 28 weeks gestation and 7-14 days after delivery. Active kilocalories during pregnancy was positively associated with fat-free mass 7-14 days after delivery. Neither structured supervised exercise training nor motivational counselling on PA during pregnancy affected maternal body composition at 28 weeks gestation or 7-14 days after delivery compared to standard care. Interestingly, when adjusted for pre-pregnancy BMI, higher number of daily steps was associated with lower fat content during pregnancy and after delivery, whereas MVPA and active kilocalories were not. Trial registration: ClinicalTrials.gov; NCT03679130; 20/09/2018.

Non-invasive technology to assess hydration status in advanced cancer to explore relationships between fluid status and symptoms: an observational study using bioelectrical impedance analysis.

BACKGROUND: Oral fluid intake decreases in advanced cancer in the dying phase of illness. There is inadequate evidence to support the assessment, and management, of hydration in the dying. Bioelectrical impedance analysis (BIA) is a body composition assessment tool. BIA has the potential to inform clinal management in advanced cancer, by examining the relationships between hydration status and clinical variables. AIM: BIA was used to determine the association between hydration status, symptoms, clinical signs, quality-of-life and survival in advanced cancer, including those who are dying (i.e. in the last week of life). MATERIALS AND METHODS: We conducted a prospective observational study of people with advanced cancer in three centres. Advance consent methodology was used to conduct hydration assessments in the dying. Total body water was estimated using the BIA Impedance index (Height - H (m)2 /Resistance - R (Ohms)). Backward regression was used to identify factors (physical signs, symptoms, quality of life) that predicted H2/R. Participants in the last 7 days of life were further assessed with BIA to assess hydration changes, and its relationship with clinical outcomes. RESULTS: One hundred and twenty-five people participated (males n = 74 (59.2%), females, n = 51 (40.8%)). We used backward regression analysis to describe a statistical model to predict hydration status in advanced cancer. The model demonstrated that 'less hydration' (lower H2/R) was associated with female sex (Beta = -0.39, p < 0.001), increased appetite (Beta = -0.12, p = 0.09), increased dehydration assessment scale score (dry mouth, dry axilla, sunken eyes - Beta = -0.19, p = 0.006), and increased breathlessness (Beta = -0.15, p = 0.03). 'More hydration' (higher H2/R) was associated with oedema (Beta = 0.49, p < 0.001). In dying participants (n = 18, 14.4%), hydration status (H2/R) was not significantly different compared to their baseline measurements (n = 18, M = 49.6, SD = 16.0 vs. M = 51.0, SD = 12.1; t(17) = 0.64, p = 0.53) and was not significantly associated with agitation (rs = -0.85, p = 0.74), pain (rs = 0.31, p = 0.23) or respiratory tract secretions (rs = -0.34, p = 0.19). CONCLUSIONS: This is the first study to use bioimpedance to report a model (using clinical factors) to predict hydration status in advanced cancer. Our data demonstrates the feasibility of using an advance consent method to conduct research in dying people. This method can potentially improve the evidence base (and hence, quality of care) for the dying. Future BIA research can involve hydration assessment of cancers (according to type and stage) and associated variables (e.g., stage of illness, ethnicity and gender). Further work can use BIA to identify clinically relevant outcomes for hydration studies and establish a core outcome set to evaluate how hydration affects symptoms and quality-of-life in cancer.

Effects of Different Resistance Training Frequencies on Body Composition, Muscular Strength, Muscle Quality, and Metabolic Biomarkers in Sarcopenic Older Women.

ABSTRACT: Dos Santos, VR, Antunes, M, dos Santos, L, Nascimento, MA, Pina, FLC, Carneiro, NH, Trindade, MCC, Venturini, D, Barbosa, DS, and Cyrino, ES. Effects of different resistance training frequencies on body composition, muscular strength, muscle quality, and metabolic biomarkers in sarcopenic older women. J Strength Cond Res 38(9): e521-e528, 2024-Resistance training (RT) can ameliorate outcomes related to sarcopenia by promoting beneficial changes in muscular strength, skeletal muscle mass (SMM), and muscle quality. This study compared the effects of 12 weeks of RT performed 2 and 3 sessions a week on body composition, muscular strength, muscle quality, and metabolic biomarkers in sarcopenic older women. Thirty-four sarcopenic older women (>60 years) were randomly assigned to perform a whole-body RT program, either 2 (G2X, n = 18) or 3 (G3X, n = 16) sessions a week during 12 weeks (8 exercises, single set of 10-15 repetitions). Body composition, muscular strength, muscle quality, and metabolic biomarkers were assessed before and after the intervention. Both groups increased (p < 0.05) 1 repetition maximum total muscular strength (G2X = +20.4% and G3X = +21.0%), SMM (G2X = +4.0% and G3X = +7.0%), and improved muscle quality (G2X = +16.7% and G3X = +13.6%), with no differences between groups (p > 0.05). No change over time was found for IGF-1 and testosterone (p > 0.05). Our results suggest that 12 weeks of RT performed at a lower weekly frequency is as effective as a higher frequency in improving muscular strength, SMM, and muscle quality in sarcopenic older women.

Estimation equation of limb lean soft tissue mass in Asian athletes using bioelectrical impedance analysis.

BACKGROUND: The lean soft tissue mass (LSTM) of the limbs is approximately 63% of total skeletal muscle mass. For athletes, measurement of limb LSTM is the basis for rapid estimation of skeletal muscle mass. This study aimed to establish the estimation equation of LSTM in Asian athletes using bioelectrical impedance analysis (BIA). METHODS: A total of 198 athletes (121 males, 77 females; mean age 22.04 ± 5.57 years) from different sports in Taiwan were enrolled. A modeling group (MG) of 2/3 (n = 132) of subjects and a validation group (VG) of 1/3 (n = 68) were randomly assigned. Using the InBody S-10, resistance and reactance were measured at 50 kHz from the right palm to the right sole while the participant was in the supine position. Predictor variables were height (h), weight (W), age, Sex, Xc, resistance index (RI; RI = h2 / R). LSTM of arms and legs measured by dual-energy X-ray absorptiometry (DXA) was the response variable. Multivariate stepwise regression analysis method was used to establish BIA estimation equations as ArmsLSTMBIA-Asian and LegsLSTMBIA-Asian. Estimation equations performance was confirmed by cross-validation. RESULTS: Estimation equation "ArmsLSTMBIA-Asian = 0.096 h2/R- 1.132 Sex + 0.030 Weight + 0.022 Xc- 0.022 h + 0.905, r2 = 0.855, SEE = 0.757 kg, n = 132" and "LegsLSTMBIA Asian = 0.197h2/R" + 0.120 h- 1.242 Sex + 0.055 Weight- 0.052 Age + 0.033 Xc -16.136, r2 = 0.916, SEE = 1.431 kg, n = 132" were obtained from MG. Using DXA measurement results of VG for correlation analysis and Limit of Agreement (LOA) of Bland-Altman Plot, ArmsLST is 0.924, -1.53 to 1.43 kg, and LegsLST is 0.957, -2.68 to 2.90 kg. CONCLUSION: The established single-frequency BIA hand-to-foot (whole body) estimation equation quickly and accurately estimates LSTM of the arms and legs of Asian athletes.

Effects of aerobic exercise combined with resistance training on body composition and metabolic health in children and adolescents with overweight or obesity: systematic review and meta-analysis.

Background: To systematically review the effects of aerobic exercise and resistance training on Metabolic Health in children and adolescents with overweight/obesity. Methods: Employing a retrieval strategy that combines subject terms and free terms, searches were conducted in the CNKI, WanFangData, VIP, PubMed, Web of Science, Embase, and Cochrane Library databases up to October 31, 2023. Results: A total of 29 studies involving 2,195 subjects were included. The combination of aerobic and resistance training significantly reduces body composition and metabolic health in children and adolescents with overweight or obesity, as evidenced by changes in various parameters (BMI, WC, FM, BF%, VO2max, TG, TC, HDL-C, LDL-C, HOMA-IR, FPG, INS). However, there were no significant differences observed in hs-CRP. Subgroup analyses further showed that changes in intervention measurement had a significant effect on the effectiveness of the intervention. Conclusion: Aerobic exercise combined with resistance training has a positive impact on the physical health of children and adolescents with overweight/obesity. The recommended exercise prescription is at least three sessions of more than 60 min per week for 12 weeks or more for better health benefits.

Association between muscle-localized bioelectrical impedance analysis parameters and performance in a multi-set exercise on the isokinetic dynamometer in young women.

This study aimed to verify the relationship between changes in thigh muscle-localized bioelectrical impedance analysis (ML-BIA) parameters and performance in a multiple-set exercise. The sample consisted of 30 female university students (22.1 ± 3.2 years). The ML-BIA parameters, including localized muscle resistance (ML-R), reactance (ML-Xc), and phase angle (ML-AngF), were evaluated using a tetrapolar bioelectric impedance device operating at a frequency of 50 KHz. The multiple sets protocol was performed with an isokinetic dynamometer. For body composition, total and leg lean soft tissue (LST) were evaluated using dual X-ray absortiometry. Student's t-test for paired samples was used to compare the ML-BIA parameters and thigh circumference pre and postexercise. Linear regression analysis was performed to verify the ∆ML-PhA as a predictor of peak torque for the three sets alone while controlling for total and leg LST. There were differences in the ML-R (∆ = 0.02 ± 1.45 Ω; p = 0.001; and E.S = 0.19), ML-Xc (∆ = 2.90 ± 4.12 Ω; p = 0.043; and E.S = 0.36), and thigh circumference (∆ = 0.82 ± 0.60 cm; p < 0.001; and E.S = 0.16) pre- and post-multiple sets. ΔML-PhA was a predictor of performance in the first set (p = 0.002), regardless of total and leg LST. However, the ΔML-PhA lost its explanatory power in the other sets (second and third), and the variables that best explained performance were total and leg LST. The ML-BIA (ML-R and ML-Xc) parameters were sensitive and changed after the multiple sets protocol, and the ΔML-PhA was a predictor of performance in the first set regardless of the total and leg LST.

The Relationship between Psychological Stress and Anthropometric, Biological Outcomes: A Systematic Review.

Background and Objectives: Challenges and threats to global security and the growing demands of today's society lead to significantly increased exposure to stress. Stress can negatively affect numerous physiological processes, including metabolic changes. An unhealthy lifestyle might intensify this disruption. The aim of the systematic review was to establish the effect of psychological stress on metabolic and anthropometric factors in healthy individuals. Materials and Methods: The study was conducted according to the PRISMA guidelines; and the risk of bias (ROB) assessment was based on the Newcastle-Ottawa Scale (NOS). A literature search of the MEDLINE/PubMed database was conducted using specific search terms. Results: We identified 32 articles meeting the inclusion criteria for the review with the different experimental designs and aims. Most of the papers were at high ROB. The included studies were conducted in groups of adults and children/teenagers. The most-often-applied tool to measure stress severity was the Perceived Stress Scale (PSS). Twenty-two studies analyzed the connection between stress and body composition, and bioimpedance analysis (BIA) was the most often used method. For biological parameters, the most frequently analyzed was cortisol (n = 9). The other examined factors included glucose, insulin, parameters related to food intake regulation, carbohydrates, lipid metabolism, inflammation, and oxidative stress. The included studies were incompliance in relation to the assessment method and type of assessed biological fluids. Conclusions: The vast majority of studies do not support the effect of chronic distress on anthropometric measurements and biological markers levels. However, many of them suggest adverse, synergistic effects of unhealthy lifestyle patterns and the stress on the examined variables. Further experiments should implement a similar and repeatable methodology.

Omnivore and vegetarians show similar body composition and skin physiology across body regions-A comparative analysis.

BACKGROUND: Skin physiology seems to be influenced by dietary choices and body composition, although links between these factors remain poorly characterised. In the present manuscript, we elaborate on the potential relationships among food groups, body composition and skin physiology in omnivores and vegetarians. MATERIAL AND METHODS: This cross-sectional observational study involved 181 participants, 129 omnivores and 52 vegetarians. The main functions of the skin measured in our laboratory were transepidermal water loss, deep and superficial epidermal hydration, skin elasticity, and carotenoid content. Skin variables obtained from different body regions were made comparable by a new Proportional Skin Index calculated to respect their relative representativity. RESULTS: No statistical differences were found when comparing both groups' body composition and skin variables from different body regions, with the exception of the skin carotenoid content significantly higher in the vegetarian group (p < 0.001). CONCLUSION: Although dietary patterns significantly differed between groups, with vegetarians consuming fewer animal-derived products and more plant-based foods, multiple linear regression analysis revealed no differences or association between the dietary pattern and the skin physiology. These findings highlight the need for further research to elucidate the specific impact of diet and food groups and body composition on skin physiology.

[Bioimpedance analysis of body composition and rest energy expenditure in highly trained cross-country skiers].

The body composition monitoring using bioimpedance analysis (BIA) is important in assessing the functional state of athletes in sports. Based on changes of body composition, it is possible to optimize the actual dietary intake, as well as successfully organize the training process. The purpose of this research was to conduct a comparative assessment of BIA parameters and rest energy expenditure (REE) in highly trained cross-country skiers and young non-athletes. Material and methods. The members of the national cross-country skiing team from the Komi Republic and Russian Federation (n=30; age - 22.3±2.7 years) were examined. Practically healthy medical students served as a control group for the present study (n=40; age - 20.2±2.4 years). The participants successively passed the following study steps: assessment of the body composition by BIA (ACCUNIQ BC380), REE determination by indirect non-fasting calorimetry and calculation technique. Results. The parameters of total body water, fat-free mass, lean tissue and body cell mass were higher in contrast to the fat mass percentage in the athletes (р<0.001). The calculated REE was lower than measured REE among all the participants. At the same time, the REE calculated by the Ketch-McArdle formula significantly differed between the groups, while no differences were found between the REE calculated by the Harris-Benedict prediction equation. The measured REE were significantly higher by 16% (p<0.001) i n athletes compared to those in the control group. Conclusion. The body composition of athletes was distinguished by a significantly higher amounts of total body water, fat-free mass, skeletal muscle, active cell mass, and lower percentage of fat mass compared to healthy untrained individuals. The results obtained among athletes coincided with the idea that the magnitude of REE is determined by the mass of metabolically active tissues and to a lesser extent depends on the fat mass. BIA results can be used to monitor athletes' body composition during the training process.

The Influence of the Energy Intake Variability During the Week on the Body Composition in an Adult Population.

Background: The regularity of eating, together with other nutritional factors, is one of the important determinants of health. According to previous studies, it is not clear if a greater fluctuation in energy intake is associated with higher body fat and weight gain, or if the weight of people is stable despite these fluctuations in the energy intake. The aim of the study was to verify if a higher variability in the energy intake each day of the week is related to the amount of body fat and other anthropometric parameters. Methods: A total of 220 (151 women, 69 men) individuals of Czech Caucasian origin with a BMI of 18.3-58 kg/m2, aged 21.7-79.7 were included in the study. Selected anthropometric characteristics were measured using a bioelectrical impedance analysis. 7-day food records were completed and analyzed using nutritional software. The measured values were statistically evaluated by multiple linear regression analysis. Results: The results of the multiple linear regression showed the statistically significant dependence of the percentage of body fat (p<0.01), BMI (p<0.01), and waist circumference (p<0.05) on the relative variability of the daily energy intake. Conclusions: The results of our study suggest that people with more regular energy intake also have better anthropometric parameters related to their cardiometabolic health.

A 3 MHz Low-Error Adaptive Howland Current Source for High-Frequency Bioimpedance Applications.

Bioimpedance is a diagnostic sensing method used in medical applications, ranging from body composition assessment to detecting skin cancer. Commonly, discrete-component (and at times integrated) circuit variants of the Howland Current Source (HCS) topology are employed for injection of an AC current. Ideally, its amplitude should remain within 1% of its nominal value across a frequency range, and that nominal value should be programmable. However, the method's applicability and accuracy are hindered due to the current amplitude diminishing at frequencies above 100 kHz, with very few designs accomplishing 1 MHz, and only at a single nominal amplitude. This paper presents the design and implementation of an adaptive current source for bioimpedance applications employing automatic gain control (AGC). The "Adaptive Howland Current Source" (AHCS) was experimentally tested, and the results indicate that the design can achieve less than 1% amplitude error for both 1 mA and 100 µA currents for bandwidths up to 3 MHz. Simulations also indicate that the system can be designed to achieve up to 19% noise reduction relative to the most common HCS design. AHCS addresses the need for high bandwidth AC current sources in bioimpedance spectroscopy, offering automatic output current compensation without constant recalibration. The novel structure of AHCS proves crucial in applications requiring higher ß-dispersion frequencies exceeding 1 MHz, where greater penetration depths and better cell status assessment can be achieved, e.g., in the detection of skin or breast cancer.

Dietary characteristics of urban community-dwelling older adults with low muscle mass: the bunkyo health study: a cross-sectional study.

BACKGROUND: With the aging of the population worldwide, extending healthy life expectancy is an urgent issue. Muscle mass has been reported to be associated with physical independence and longevity. This study aimed to investigate the characteristics of food intake in urban community-dwelling older adults with low muscle mass. METHODS: This cross-sectional study used baseline data from the Bunkyo Health Study, which included 1618 urban community-dwelling older adults aged 65-84 years. All participants underwent measurement of body composition using bioelectrical impedance analysis and evaluation of nutrient and food intake using the brief-type self-administered diet history questionnaire. Participants were stratified by sex and divided into robust or low skeletal muscle mass index (SMI) groups according to the Asian Working Group for Sarcopenia criteria to compare differences in nutrient and food intake. RESULTS: The mean age and body mass index were 73.1 ± 5.4 years and 22.6 ± 3.1 kg/m2, respectively. The prevalence of low SMI was 31.1% in men and 43.3% in women. In men, all food intake, including total energy intake, was similar between the low SMI group and the robust group. In women, the low SMI group had less total energy intake, and consumed lower amounts of energy-producing nutrients (protein, fat, and carbohydrates), but there were only small differences in the intake of specific foods. CONCLUSIONS: There were sex differences in food intake characteristics between urban community-dwelling older adults with low SMI and those who were robust. Advising women to increase their energy intake may be important in preventing muscle loss, and further research is needed in men.

Effects of physical inactivity behavior during COVID-19 pandemic on physical fitness, body composition, inflammatory cytokine, and immunocytes in older adults: A retrospective and prospective study.

The prolonged period of COVID-19 has ingrained physical inactivity as a habit, leading to a reluctance to move. This has resulted in a decline in physical fitness and the loss of a healthy body composition. While this trend is particularly noticeable among the older adults, its impact on the immune cell defense system, which is crucial for minimizing viral infections, remains unclear. This study aimed to investigate the physical fitness, body composition, cytokines and immunocytes of older adults who engaged in physical activity (PA) before the COVID-19 pandemic but had to stop it due to the lockdown. A total of 172 older adults aged 61 to 85 years participated in this study: 90 in non-PA group (NPAG, 34 men and 56 women), and 82 in PA group (PAG, 29 men and 53 women). Physical inactivity was 45.13 ± 5.67 weeks in the NPAG and 1.70 ± 0.43 weeks in the PAG. Although there was no significant difference in calorie intake, PA volume showed a significant decrease in NPGA (P < 0.001). VO2max, strength, and sit-ups decreased in NPAG, whereas they maintained or increased in PAG (Ps < 0.001). NPAG experienced an increase in fat mass (∼33.0 %), along with a decrease in muscle mass (∼10.4 %), but PAG showed slight increases (∼1.1 % vs. ∼1.5 %, Ps < 0.001). Interleukin-6 (∼38.9 %), tumor necrosis factor-α (∼38.3 %), and C-reactive protein (∼33.6 %) increased, whereas immunocytes decreased in NPAG (Ps < 0.001). In contrast, those in PAG showed the opposite phenomenon. This study indicates that even during the COVID-19 situation, maintaining active PA in the older adults helps retain beneficial physical fitness and body composition, reduces inflammatory factors, and contributes to preserving or enhancing the function of immunocytes.

Efficacy of Supersets Versus Traditional Sets in Whole-Body Multiple-Joint Resistance Training: A Randomized Controlled Trial.

ABSTRACT: Iversen, VM, Eide, VB, Unhjem, BJ, and Fimland, MS. Efficacy of supersets versus traditional sets in whole-body multiple-joint resistance training: A randomized controlled trial. J Strength Cond Res 38(8): 1372-1378, 2024-Time constraints often hinder exercise engagement, necessitating exploration of time-efficient resistance training methods. Superset training, where 2 exercises are performed successively with minimal rest, nearly halves session duration but is metabolically demanding, possibly reducing strength gains. In a randomized controlled trial with blinded test leaders, we examined the efficacy of supersets versus traditional sets in a full-body, multiple-joint resistance training workout on maximal strength in the trained exercises. Subjects took part in a 3-week introductory training phase before baseline testing to ensure they were thoroughly familiarized. Next, they were randomized to a superset- or a traditional-set group, performing 10 weeks of heavy multiple-joint resistance training twice per week. The exercise programs consisted of leg press, bench press, lat pull-down, and seated rows. The traditional training group had a 5.2-kg higher improvement in pull-down than the superset group (p = 0.033), and a close to significant 4.8-kg higher improvement in seated rows (p = 0.073). The improvements in leg press and bench press were quite similar for both groups (p = 0.507-0.527). There were no changes between groups in body composition outcomes (0.151-0.640), but both groups increased muscle mass and reduced fat mass (p < 0.05). In conclusion, superset training of multi-joint exercises hampered maximal strength gains somewhat compared with traditional-set training. However, there were very similar improvements in body composition, and strength gains were observed for all exercises in the superset group. Thus, whole-body, multiple-joint superset resistance training could be a viable time-saving approach.

Validation of Bioelectrical Impedance Devices for the Determination of Body Fat Percentage in Firefighters.

ABSTRACT: Jagim, AR, Luedke, J, Erickson, JL, Fields, JB, and Jones, MT. Validation of bioelectrical impedance devices for the determination of body fat percentage in firefighters. J Strength Cond Res 38(8): e448-e453, 2024-To cross-validate bioelectrical impedance devices for the determination of body fat percentage (BF%) in firefighters. Twenty-eight structural firefighters were evaluated (female, n = 2; male, n = 26 [mean ± SD] age: 38.2 ± 8.3 years; height: 180.2 ± 7.5 cm; body mass: 86.7 ± 20.8 kg; body mass index: 25.8 ± 7.8 kg·m-2) using multifrequency bioelectrical impedance analysis (MFBIA) hand-to-foot device, and single-frequency BIA foot scale (F2FBIA), and a single-frequency handheld BIA device (HHBIA). Dual X-ray absorptiometry served as the criterion. Validity metrics were examined to establish each method's performance. Body fat % values produced by MFBIA (r = 0.913), F2FBIA (r = 0.695), and HHBIA (r = 0.876) were strongly associated (p < 0.001) with criterion BF% measures. However, MFBIA, F2FBIA, and HHBIA all significantly (p < 0.001) underestimated BF% when compared with the criterion measure. Constant error ranged between 4.0 and 5.5% across all BIA devices. Despite strong associations between the BIA devices included in the current study and the criterion measure, all BIA devices underestimated BF%, which resulted in an overestimation of fat-free mass. In addition, proportional bias was observed in which BF% was overestimated at lower values and underestimated at higher values.

Sarcopenic obesity and pre-sarcopenia contribute to frailty in community-dwelling Italian older people: data from the FRASNET study.

BACKGROUND: The ageing process is characterized by a change of body composition with an increase of fat mass and a reduction of muscle mass. Above a certain threshold these alterations configure a condition named sarcopenic obesity (SO). SO is associated with physical frailty in Asian and Brazilian populations. SO impacts on physical frailty in other ethnic groups but its influence on general frailty which is multidimensional and includes cognitive, social and physical factors, remain insufficiently explored in the Italian population. METHODS: Frailty was measured in community dwelling Italian older adults enrolled in the FRASNET study with the frailty index (FI). The FI quantifies frailty as the ratio of the number of present health deficits to the total number of health deficits considered. Regression analyses were performed to assess the association between body composition categories and frailty. Classification and regression tree models were run to evaluate the frailty predictors. RESULTS: One Thousand One Hundred Fourteen participants of the FRASNET study were included in the present analysis. The sample was composed for the 60.5% by females and its median age was 72 years. The median FI score was 0.11 (IQR 0.07-0.20); 234 individuals (21%) were frail (FI ≥ 0.25). SO (B 0.074, 95% C.I. 0.05-0.1, p < 0.001) and pre-sarcopenia (without obesity B 0.03, 95% C.I, 0.007-0.044, p < 0.001, with obesity B 0.11, 95% C.I. 0.05-0.16, p < 0.001) were associated with frailty. Fat mass percentage predicted frailty in people aged 65-70 years whereas, muscle strength predicted general frailty in people aged 70-81 years. CONCLUSION: Pre-sarcopenia and SO represent potentially treatable predictors of frailty.

Associations of muscle mass and strength with depression among US adults: A cross-sectional NHANES study.

OBJECTIVES: The aim of our study was to assess the association between muscle mass and strength and depression through a cross-sectional study of the National Health and Nutrition Examination Survey from 2011 to 2014. METHODS: Muscle mass was calculated by summing the lean body mass of the limbs and muscle strength was assessed by grip strength. Depression was determined by The 9-item Patient Health Questionnaire. We used weighted multivariate logistic regression models to explore the relationship between muscle mass and strength and depression. Generalized additive models were used to test for the presence of nonlinear associations. We then constructed a two-piece-wise linear regression model and performed a recursive algorithm to calculate inflection points. In addition, subgroup analyses and interaction tests were performed. RESULTS: The study recruited 4871 adults from the United States. In regression models adjusted for all confounding variables, the OR (95 % CI) for the association between grip strength and appendicular lean mass (ALM) and depression were 0.943 (0.903, 0.985), 0.945 (0.908, 0.983), respectively. There was a non-linear association between grip strength and depression with a turning point of 46.3. The OR (95 % CI) before the turning point was 0.920 (0.872, 0.972). The interaction was statistically significant only in the age analysis. There was also a nonlinear association between ALM and depression, but no significant turning point was found. The interaction was statistically significant in the gender and BMI analyses. CONCLUSION: Grip strength and ALM are negatively associated with an increased likelihood of depression in US adults. Exercises for muscle mass and strength may help prevent depression.