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[Display omitted] • This study explored the effects of 12-week chlorella vulgaris (CV) combined with interval resistance training (IRT) on plasma levels of leptin, adiponectin and neuregulin-4 (Nrg-4) in obese men. • The main finding of our study is that the combination of CV and IRT increased Nrg-4 and adiponectin levels while also decreasing leptin levels in obese participants. • These findings provide evidence that a combination of IRT and CV can modulate the levels of some adipokines (leptin, adiponectin and Nrg-4) in obese men. To evaluate the effects of 12-week chlorella vulgaris (CV) combined with interval resistance training (IRT) on plasma levels of leptin, adiponectin and neuregulin-4 (Nrg-4) in obese men. Obese men (n = 44, BMI of 32.1 ± 1.5 kg/m2) were randomly allocated to the following groups of 11 participants per group: Control Placebo group (CP), CV supplement group (CV), Interval Resistance Training group plus Placebo (IRT + P), and Interval Resistance Training plus CV supplement group (IRT + CV). IRT was performed three times a week for 12 weeks using three sets of 10 repetitions at 60 % 1RM, and integrating an active rest interval with 15 repetitions at 20 % 1RM. Participants consumed either CV (1800 mg daily) or a placebo. Pre- and post-intervention blood samples were obtained to assess adipokines which were measured by ELISA. While CV or IRT separately did not alter plasma levels of leptin (p > 0.05), their combination reduced leptin levels (p = 0.007). IRT and IRT plus CV increased the plasma levels of adiponectin and Nrg-4 (p < 0.01). An intergroup comparison indicated significant elevations of adiponectin and Nrg-4 in the CV compared to the CP group (p < 0.05). The combination of IRT and CV modulates plasma levels of leptin, adiponectin and NRG4 more effectively than either IRT or CV separately in obese men. [ABSTRACT FROM AUTHOR]

Interventional studies offer strong evidence for exercise's osteogenic impact on bone particularly during growth. With rising osteoporosis rates in older women, enhancing bone strength early in life is crucial. Thus, investigating the osteogenic effects of different types of physical activities in young females is crucial. Despite varied findings, only two systematic reviews tried to explore this topic without examining how different types of exercise may affect bone health in adolescent girls. The first aim of this systematic review was to assess the impact of exercise training on bone health parameters in adolescent girls, and the second aim was to investigate whether the type of exercise training can modulate this effect. A systematic literature search was conducted using common electronic databases from inception - January 2023. Seven studies (355 participants) were eligible for inclusion in this systematic review. Two studies dealt with resistance training, 3 studies applied plyometric training, 1 study used team sports, and 1 study used dancing. Results indicate that plyometric training increases lumbar spine bone mass in adolescent girls. Well-designed randomized controlled trials with a proper training period (> 12 weeks) are needed to advocate a specific type of training which has the highest osteogenic effect. [ABSTRACT FROM AUTHOR]

Objectives: Determine the influence of movement profile on systemic stress and mechanical loading before and after high training load exposure.Design: Cross-sectional cohort study.Methods: 43 physically active, college-aged field or court sport female athletes participated in this study. Participants were assigned to a "excellent" (n=22; age=20.5±1.9yrs, height=1.67±0.67m, mass=64.5±7.8kg) or "poor" (n=21; age=20.4±1.3yrs, height=1.69±0.67m, mass=60.9±6.1kg) movement group defined by The Landing Error Scoring System. Participants completed five cycles of high training load exercise of 5-min treadmill-running at a speed coincident with 100-120% ventilatory threshold and 10 jump-landings from a 30-cm box. Jump-landing vertical ground reaction force and serum cortisol were evaluated prior to and following exercise. Vertical ground reaction force ensemble averages and 95% confidence interval waveforms were generated for pre-exercise, post-exercise, and pre-post exercise changes. A two-way mixed model ANOVA was used to evaluate the effect of movement profile on systemic stress before and after exercise.Results: There was no significant difference in changes in serum cortisol between the poor and excellent groups (p=0.69) in response to exercise. Overall, individuals in the poor group exhibited a higher serum cortisol level (p<0.05, d=0.85 [0.19,1.48]). The poor group exhibited higher magnitude vertical ground reaction force prior to (d=1.02-1.26) and after exercise (d=1.15) during a majority of the stance phase.Conclusions: Individuals with poor movement profiles experience greater mechanical loads compared to individuals with excellent movement profiles. A poor movement profile is associated with greater overall concentrations of circulating cortisol, representative of greater systemic stress. [ABSTRACT FROM AUTHOR]

Abstract: Increased adiposity is associated with insulin resistance (IR) and an inflammatory response in adults. We tested the hypotheses that cytokines associated with adiposity are also correlated with IR in early adolescents and that these relationships are moderated by weight status, levels of vigorous physical activity (VPA), or maximal aerobic power (pVO2max). Body mass, stature, and a fasting blood sample were obtained from 120 midpubertal adolescents (60 girls and 60 boys). Habitual VPA was obtained by a survey. Predicted VO2max was determined using a cycle ergometer test. Weight status was based on body mass index (BMI) percentiles (normal weight = BMI <75th percentile, overweight = BMI >95th percentile). Glucose, insulin, adiponectin, resistin, tumor necrosis factor–α (TNF-α), and interleukin-6 were measured; and IR index was based on the Homeostatic Model Assessment. Adiponectin, resistin, and TNF-α were associated with IR in all adolescents (R 2 = 0.329, P < .001; R 2 = 0.152, P = .001; and R 2 = 0.141, P = .002; respectively); but interleukin-6 was not (R 2 = 0.148, P = .114). The degree of association between adiponectin and IR was stronger in overweight than in normal-weight adolescents (P < .050). When regression models included weight status, neither TNF-α nor resistin was significantly related to IR (P > .050). Exercise did not moderate the association between these cytokines and IR. However, higher levels of VPA and/or pVO2max were associated with higher adiponectin, lower resistin, and lower TNF-α in at least one of the sexes. Our results indicate that the pathophysiology of obesity is already established in early adolescents. Increased adiposity, resulting in reduced adiponectin and increased resistin and TNF-α, may link these cytokines with IR in adolescents. [Copyright &y& Elsevier]

Abstract Background Aberrant mechanical loading during gait is hypothesized to contribute to the development of posttraumatic osteoarthritis following anterior cruciate ligament reconstruction. Our purpose was to determine if peak vertical ground reaction force and instantaneous vertical ground reaction force loading rate associate with the acute change in serum cartilage oligomeric matrix protein following a 20-minute bout of walking. Methods We enrolled thirty individuals with a unilateral anterior cruciate ligament reconstruction. Peak vertical ground reaction force and instantaneous vertical ground reaction force loading rate were extracted from the first 50% of the stance phase of gait during a 60-second trial. Blood samples were collected immediately before and after 20 min of treadmill walking at self-selected speed. The change in serum cartilage oligomeric matrix protein from pre- to post-walking was calculated. Stepwise linear regression models were used to determine the association between each outcome of loading and the change in serum cartilage oligomeric matrix protein after accounting for sex, gait speed, time since anterior cruciate ligament reconstruction, graft type, and history of concomitant meniscal procedure (ΔR2). Findings Lesser peak vertical ground reaction force (ΔR2 = 0.208; β = −0.561; P = 0.019) and instantaneous vertical ground reaction force loading rate (ΔR2 = 0.168; β = −0.519; P = 0.037) on the anterior cruciate ligament reconstructed limb associated with a greater increase in serum cartilage oligomeric matrix protein following 20 min of walking. Interpretation Mechanical loading may be a future therapeutic target for altering the acute biochemical response to walking in individuals with an anterior cruciate ligament reconstruction. Highlights • Lesser magnitude of loading associated with a greater biochemical response after walking. • Lesser instantaneous rate of loading was associated with a greater biochemical response. • Limb symmetry of loading characteristics was not associated with the biochemical response. [ABSTRACT FROM AUTHOR]

We compared the acute response and recovery of ultrasonography (US) cartilage outcomes (i.e., thickness, cross-sectional area, and echo intensity) between walking, drop-landing and control conditions in 43 young adults with no history of lower extremity injury. A femoral cartilage US assessment was performed before and after each condition to determine the acute cartilage response and recovery at 15, 30 and 45 min. Percentage change scores from pre- to all post-time points were used for analysis. Acute cartilage response and recovery were analyzed with a 3 × 4 (condition × time) repeated-measures analysis of variance. Greater deformation of the medial and lateral femoral cartilage was observed immediately after both the walking and drop-landing conditions compared with the control condition. Cartilage deformation after the drop-landing condition required longer time to recover compared with the walking condition. The femoral cartilage deformation was not accompanied by concurrent alterations in cartilage echo intensity. [ABSTRACT FROM AUTHOR]

This is the first report of the psychobiology of stress in BASE jumpers, one of the most dangerous forms of extreme sport. We tested the hypotheses that indicators of emotional style (temperament) predict salivary cortisol reactivity, whereas indicators of intentional goal-setting (persistence and character) predict salivary alpha-amylase reactivity during BASE jumping. Ninety-eight subjects completed the Temperament and Character Inventory (TCI) the day before the jump, and 77 also gave salivary samples at baseline, pre-jump on the bridge over the New River Gorge, and post-jump upon landing. Overall BASE jumpers are highly resilient individuals who are highly self-directed, persistent, and risk-taking, but they are heterogeneous in their motives and stress reactivity in the Hypothalamic-Pituitary-Adrenal (HPA) stress system (cortisol reactivity) and the sympathetic arousal system (alpha-amylase reactivity). Three classes of jumpers were identified using latent class analysis based on their personality profiles, prior jumping experience, and levels of cortisol and alpha-amylase at all three time points. “Masterful” jumpers (class 1) had a strong sense of self-directedness and mastery, extensive prior experience, and had little alpha-amylase reactivity and average cortisol reactivity. “Trustful” jumpers (class 2) were highly cooperative and trustful individuals who had little cortisol reactivity coincident with the social support they experienced prior to jumping. “Courageous” jumpers (class 3) were determined despite anxiety and inexperience, and they had high sympathetic reactivity but average cortisol activation. We conclude that trusting social attachment (Reward Dependence) and not jumping experience predicted low cortisol reactivity, whereas persistence (determination) and not jumping experience predicted high alpha-amylase reactivity. [ABSTRACT FROM AUTHOR]

Evidence suggests that higher testosterone levels may provide an athletic advantage. Therefore, it is of practical interest to examine the association between testosterone levels and power- and strength-related traits in young professional track and field athletes, and to consider the factors that determine testosterone levels. The study involved 68 young professional athletes (45 females, 17.3 ± 2.6 years; 23 males, 18.2 ± 1.9 years). Testosterone levels were assessed via liquid chromatography-mass spectrometry. All subjects performed two 20 m and two 30 m sprint trials, and countermovement jump without arm-swing. A bioimpedance analysis of body composition was carried out and biological maturity was examined using the Khamis-Roche method. The average testosterone levels were 26.4 ± 9.6 nmol/l and 1.5 ± 0.7 nmol/l in males and females, respectively. In female athletes, testosterone levels did not correlate with any of traits. Males with the highest testosterone levels were significantly faster in the 20 m (p = 0.033) and 30 m (p = 0.014) sprint trials compared to males with lower testosterone levels. Testosterone levels in males were positively associated with fat mass (p = 0.027), and degree of biological maturation (p = 0.003). In conclusion, we found a positive relationship between testosterone levels and sprint performance in young male athletes. [ABSTRACT FROM AUTHOR]

Herbal products and supplements use by athletes has increased over the past decade. One such item being polyphenols. These are reported to reduce weight and modify body composition, which could aid athletes in many sports. Therefore, the purpose of the study was to determine the effect of 6 weeks supplementation with carob, a naturally occurring polyphenol, on body composition and aerobic capacity in youth taekwondo athletes. Twenty-three taekwondo athletes (21.9 ± 1.2 years; 1.64 ± 0.03 m; 67.4 ± 17.3 kg;BMI: 22.8 ± 5.5 kg/m2) participated in a short-term (6-week) double-blind randomized design parallel fully controlled training study (pre-to-post measurements): Supplemented group (SG), n = 11;placebo group (PG), n = 12. Body composition, aerobic capacity, heart rate and RPE were analyzed before and after 6 weeks of carob rich polyphenol ingestion. Significantly greater decreases in weight were observed for SG and PG (−2.82% and − 0.51%respectively) with differences between groups (p < 0.001). No significant differences were reported in percentage body fat and muscular volume between groups. Our results revealed an improvement of aerobic performance score and RPE with differences between groups. A cute polyphenol supplementation seemed to be effective in reducing body weight and improving aerobic performance in athletes. [ABSTRACT FROM AUTHOR]

Abstract Purpose We studied the effect of two interval training programs of varying intensities (100% vs. 110% of maximal aerobic velocity [MAV]) on hematocrit (Ht), hemoglobin (Hb), and plasma volume variations (PVV) in young men. Methods Thirty-nine male volunteered were assigned to two control groups (CG 100 , n = 9 and CG 110 , n = 10), and two training groups (one with 100% MAV [EG 100 , n = 10] and one with 110% MAV [EG 110 , n = 10]). All participants performed a maximal graded exercise test and an intermittent exercise (IE) protocol. Blood was collected at rest, at the end of the IE and after 15 min of recovery, before and after 8-weeks-training. Interval training (IT) sessions consist of 30s IE run at 100% or 110% MAV with 30s recovery at 50% MAV. Results After training, time to exhaustion (TTE) was improved in EG 110 (+613.7) and EG 100 (+397.5). This improvement was greater in EG 110 than EG 100 (p < 0.005). After training, Hb deceased in EG 100 and EG 110 at rest (p < 0.01), at the end of IE (p = 0.000) and after 15 min of recovery (p = 0.01). This decrease was more slightly more substantial at rest in EG 100 (−0.6%) than EG 110 (−0.3%). After training, Ht decreased in EG 100 and EG 110 at rest (p = 0.001), at the end of IE (p = 0.000) and at 15 min of recovery (p = 0.01). This decrease was more important in EG 110 than EG 100 at rest (−2.7%), at the end of IE (−2.1%) and after 15 min recovery. After training, PVV rest and PVV end increased in EG 100 (+2.2%) and EG 110 (+3.2%). No significant difference between EG 100 and EG 110 was observed. Conclusion Increasing IT intensity by 10% MAV increases PVV rest and PVV end. Despite the fact that EG 100 and EG 110 had the same PVV end after training, greater performances were recorded in EG 110. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare the hormonal responses to one session of high-intensity interval training (HIIT, 4 × 4 min intervals at 85–95% maximum heart rate [HRmax], interspersed with 4 min of recovery at 75–85% HRmax), resistance training (RT at 50–70% of one repetition maximum 12–15 repetitions per set with 60s of recovery) or both (HIIT+RT) exercise protocol in a cohort of physical inactivity, overweight adults (age 18–30 years old). Randomized, parallel-group clinical trial among fifty-one men (23.6 ± 3.5 yr; 83.5 ± 7.8 kg; 28.0 ± 1.9 kg/m2), physical inactivity (i.e., <150 min of moderate-intensity exercise per week for >6 months), with abdominal obesity (waist circumference ≥90 cm) or body mass index ≥25 and ≤30 kg/m 2 were randomized to the following 4 groups: high-intensity interval training (HIIT, n = 14), resistance training (RT, n = 12), combined high-intensity interval and resistance training (HIIT+RT, n = 13), or non-exercising control (CON, n = 12). Cortisol, total- and free-testosterone and total-testosterone/cortisol-ratio (T/C) assessments (all in serum) were determined before (pre) and 1-min post-exercise for each protocol session. Decreases in cortisol levels were −57.08 (95%CI, −75.58 to −38.58; P = 0.001; ɳ 2  = 0.61) and − 37.65 (95%CI, −54.36 to −20.93; P = 0.001; ɳ 2  = 0.51) in the HIIT and control group, respectively. Increases in T/C ratio were 0.022 (95%CI, 0.012 to 0.031; P = 0.001; ɳ 2  = 0.49) and 0.015 (95%CI, 0.004 to 0.025; P = 0.007; ɳ 2  = 0.29) in the HIIT and control group, respectively. In per-protocol analyses revealed a significant change in cortisol levels [interaction effect F( 7.777 ), ɳ 2  = 0.33] and T/C ratio [interaction effect F( 5.298 ), ɳ 2  = 0.25] between groups over time. Additionally, we showed that in both the intention-to-treat (ITT) and per protocol analyses, HIIT+RT did not change serum cortisol, total or free testosterone. The present data indicate a HIIT reduced cortisol and increased total-testosterone/cortisol-ratio levels significantly in physically inactive adults. Further study is required to determine the biological importance of these changes in hormonal responses in overweight men. [ABSTRACT FROM AUTHOR]

Individuals with anterior cruciate ligament reconstruction (ACLR) often exhibit a “stiffened knee strategy” or an excessively extended knee during gait, characterized by lesser knee flexion excursion and peak internal knee extension moment (KEM). The purpose of this study was to determine the effect of real-time biofeedback (RTBF) cuing an acute change in peak vertical ground reaction force (vGRF) during the first 50% of the stance phase of walking gait on: (1) root mean square error (RMSE) between actual vGRF and RTBF target vGRF; (2) perceived difficulty; and (3) knee biomechanics. Acquisition and short-term recall of these outcomes were evaluated. Thirty individuals with unilateral ACLR completed 4 separate walking sessions on a force-measuring treadmill that consisted of a control (no RTBF) and 3 experimental loading conditions using RTBF including: (1) 5% vGRF increase (high-loading), (2) 5% vGRF decrease (low-loading) and (3) symmetric vGRF between limbs. Bilateral biomechanical outcomes were analyzed during the first 50% of the stance phase, and included KEM, knee flexion excursion, peak vGRF, and instantaneous vGRF loading rate (vGRF-LR) for each loading condition. Peak vGRF significantly increased and decreased during high-loading and low-loading, respectively compared to control loading. Instantaneous vGRF-LR, peak KEM and knee flexion excursion significantly increased during the high-loading condition compared to low-loading. Perceived difficultly and RMSE were lower during the symmetrical loading condition compared to the low-loading condition. Cuing an increase in peak vGRF may be beneficial for increasing KEM, knee flexion excursion, peak vGRF, and vGRF-LR in individuals with ACLR. Clinical Trials Number: NCT03035994. [ABSTRACT FROM AUTHOR]

Background: Both fetal growth restriction and prematurity have been associated with cardiometabolic risk in youth and adults, however, data on their combined effects on cardiometabolic health in youth are scarce.Aims: This study aimed at assessing the effects of birth weight and gestational age combined on life-course cardiovascular risk factors and obesity among schoolchildren from Colombia.Study Design: A cross-sectional study.Subjects: Participants comprised 2510 Colombian schoolchildren (54.8% girls) aged 9-17.9years.Outcome Measures: Four groups were created according to WHO criteria: those born at term with an appropriate birth weight (≥2500g to ≤4000g) for gestational age (term AGA); those born preterm (<37 to <42 completed weeks) with an appropriate birth weight for gestational age (preterm AGA); those born at term with low birth weight for gestational age (term SGA); and those born preterm with low birth weight for gestational age (preterm SGA). Anthropometric markers (body mass, height, waist circumference, and body mass index), blood pressure, lipids profile, fasting glucose, and pubertal stage were assessed. The prevalence of metabolic syndrome was determined by de Ferranti definition.Results: There were differences between the 4 groups for calendar age (p=0.011), body mass (p=0.001), height (p=0.001), and body mass index (p=0.027). Overall, preterm SGA group had a greater risk for having elevated fasting glucose and metabolic syndrome (total sample and in boys) compared with term AGA group (p<0.05). For other cardiovascular risk factors, no significant relationships were observed based on birth characteristics.Conclusions: School-age children and adolescents with combined fetal growth restriction and prematurity exhibited an increased prevalence of glucose risk and metabolic syndrome. [ABSTRACT FROM AUTHOR]

Objective: To examine the effects of exercise on serum estrogens, growth hormone, insulin, cortisol, lactate, and glucose levels in postmenopausal women receiving two routes of administration of estrogen replacement therapy (ERT).Design: Prospective, randomized, crossover study.Setting: The general clinical research center of an academic medical center.Patient(s): Eleven active, postmenopausal women.Intervention(s): The patients were screened with exercise stress testing, then oral micronized estradiol or transdermal estradiol was administered, followed by two 45-minute submaximal exercise tests. Dietary intake before the tests was standardized.Main Outcome Measure(s): The study measured maximal heart rate and aerobic power (V˙o2max), and serum levels of estradiol (E2), estrone (E1), cortisol, growth hormone (GH), insulin, glucose, and lactate.Result(s): Growth hormone, cortisol, and insulin all changed significantly in response to the 45-minute exercise bouts, but no differences were observed between the oral micronized estradiol and transdermal estradiol responses. E2 levels increased significantly during the transdermal estradiol 45-minute exercise bout; this change did not occur during the oral estradiol exercise bout. In the transdermal estradiol treatment group, the E2 levels at +30 and +45 minutes of exercise were elevated compared to the post-exercise levels at −15, 0, and 30 minutes. E1 was not significantly changed during the 45-minute exercise bouts in either group.Conclusion(s): During exercise, serum E2 levels rise significantly higher with transdermal but not oral routes of E2 administration. However, the elevated levels are not prolonged and normalize by 30 minutes after exercise. [Copyright &y& Elsevier]

• Obesity is a key health risk factor characterized by an excessive accumulation of pro-inflammatory cytokines that play a major role in the development of metabolic syndrome. • Intermittent fasting (IF) is among the popular strategies to prevent or improve obesity-related risk factors. • IF affects positively body composition and systemic inflammation biomarkers in individual with obesity. • IF could be an effective strategy modify inflammation in individual with obesity. To determine the effects of Ramadan intermittent fasting (RIF) on inflammatory (C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α)) and biochemical markers of liver-renal function (aspartate aminotransferase (AST), alanine amino transferase (ALT), bilirubin, lactate dehydrogenase (LDH), urea and creatinine) in males with obesity. Twenty-eight males with obesity were randomly allocated to an experimental group (EG, n = 14) or a control group (CG, n = 14). The EG group completed their fasting rituals for the entire month of Ramadan (30 days) whereas the CG group continued with their normal daily habits. Blood samples were collected 24 h before the start of Ramadan (T0), on the 15th day of Ramadan (T1), the day after the end of Ramadan (T2), and 21 days after the end of Ramadan (T3). Resting plasma volume variation between pre and post-RIF (ΔPV) was calculated. Decreases were noted for interleukin-6 (p = 0.02, d = 1.4) and tumor necrosis factor-alpha (p = 0.01, d = 0.7), with no changes for C-reactive protein (p = 0.3; d = 0.1) in the EG compared to CG group. There were no changes (P > 0.05) in ΔPV recorded after RIF for either EG (-0.035 ± 0.02%) and CG (0.055 ± 0.06%). This study demonstrates that RIF improves systemic inflammation biomarkers in males with obesity. Moreover, RIF did not negatively affect biomarkers of liver and renal function. [ABSTRACT FROM AUTHOR]