Comparison of acute effects of different resistance exercise protocols with and without blood flow restriction on selected hypertrophy-related hormones in competitive wrestlers

The study aimed to compare the acute effects of low resistance exercises with partial and complete blood flow restriction (BFR) and heavy resistance exercise on growth hormone (GH), myostatin, testosterone, and cortisol in competitive wrestlers. Forty elite wrestlers were randomly divided into four groups (n=10); low resistance training with complete BFR (LRT+CBFR), low resistance training with partial BFR (LRT+PBFR), low resistance training (LRT), and heavy resistance training (HRT). Blood samples were collected before and after the intervention, and a specific ELISA kit measured variables. Analysis of covariance and paired t-test was performed to analyze the data. There were no significant differences in the variables between the four interventions. Intra-group results showed a significant decrease in myostatin levels in the HRT group (p=0.02), and a significant increase in GH in the LRT+CBFR (p=0.02) and LRT+PBFR (p=0.03), testosterone in the HRT group (p=0.04) and cortisol in the three groups LRT+CBFR (p=0.02), LRT+PBFR (p=0.01) and HRT (p=0.04). Despite the similarity of the changes in the four interventions, due to the percentage of changes, it seems that low resistance training with BFR could produce similar anabolic effects to high-intensity resistance training

Effects of swimming in cold water on lipolysis indicators via fibroblast growth factor-21 in male Wistar rats

This study aimed to investigate the effects of swimming in cold water on the release of FGF21 from various tissues and its impact on fat metabolism. Twenty Wistar rats were randomly divided into three groups: untrained (C), trained in thermo-neutral water (TN, 30 °C) and trained in cold water (TC, 15 °C). The training groups swam intervals (2-3 min) until exhaustion, 1 min rest, three days a week for six weeks, with 3-6% bodyweight load. The mRNA expression of variables was determined in white fat tissue (WAT), and FGF21 protein was also measured in the liver, brown fat tissue (BAT), serum, and muscle. The experimental protocols resulted in lower body weight gain, associated with reduced WAT volume; the most remarkable improvement was observed in the TC group. Swimming significantly increased FGF21 protein levels in WAT, BAT, and muscle tissues compared to the C group; substantial increases were in the TC group. Changes in FGF21 were highly correlated with the activation of genes involved in fat metabolisms, such as CPT1, CD36, and HSL, and with glycerol in WAT. The findings indicate a positive correlation between swimming in cold water and the activation of genes involved in fat metabolism, possibly through FGF21 production, which was highly correlated with fat-burning genes

Effects of Blood Flow Restriction and Exercise Intensity on Aerobic, Anaerobic, and Muscle Strength Adaptations in Physically Active Collegiate Women

The purpose of this study was to compare the effects of different combinations of blood flow restriction (BFR) pressure and exercise intensity on aerobic, anaerobic, and muscle strength adaptations in physically active collegiate women. Thirty-two women (age 22.8 ± 2.9 years; body mass index 22.3 ± 2.7 kg/m2) were randomly assigned into four experimental training groups: (a) increasing BFR pressure with constant exercise intensity (IP-CE), (b) constant partial BFR pressure with increasing exercise intensity (CPp-IE), (c) constant complete BFR pressure with increasing exercise intensity (CPC-IE), and (d) increasing BFR pressure with increasing exercise intensity (IP-IE). The participants completed 12 training sessions comprised of repeated bouts of 2 min running on a treadmill with BFR interspersed by 1-min recovery without BFR. Participants completed a series of tests to assess muscle strength, aerobic, and anaerobic performances. Muscle strength, anaerobic power, and aerobic parameters including maximum oxygen consumption (VO2max), time to fatigue (TTF), velocity at VO2max (vVO2max), and running economy (RE) improved in all groups (p ≤ 0.01). The CPC-IE group outscored the other groups in muscle strength, RE, and TTF (p < 0.05). In summary, participants with complete occlusion experienced the greatest improvements in muscle strength, aerobic, and anaerobic parameters possibly due to increased oxygen deficiency and higher metabolic stress

Blood Flow Restriction During Futsal Training Increases Muscle Activation and Strength

The aim of this study was to investigate the effect of leg blood flow restriction (BFR) applied during a 3-a-side futsal game on strength-related parameters. Twelve male futsal players were randomly assigned into two groups (n = 6 for each group) during 10 training sessions either with or without leg BFR. Prior to and post-training sessions, participants completed a series of tests to assess anabolic hormones and leg strength. Pneumatic cuffs were initially inflated to 110% of leg systolic blood pressure and further increased by 10% after every two completed sessions. In comparison with baseline, the resting post-training levels of myostatin (p = 0.002) and IGF-1/MSTN ratio (p = 0.006) in the BFR group changed, whereas no change in the acute level of IGF-1 and myostatin after exercise was observed. Peak torque of knee extension and flexion increased in both groups (p &lt; 0.05). A trend of increased neural activation of all heads of the quadriceps was observed in both groups, however, it was statistically significant only for rectus femoris in BFR (p = 0.02). These findings indicated that the addition of BFR to normal futsal training might induce greater neuromuscular benefits by increasing muscle activation and augmenting the hormonal response

The role of the cultural environment in the development of physical literacy and physical activity of Iranian children

Abstract Background The investigation of physical literacy (PL) and physical activity (PA) should be done in an ecological context because the socio-cultural situation can encourage or inhibit children’s activity. The present study aimed to study the role of the cultural environment in the development of PL and PA in Iranian children. Methods The statistical population consisted of Iranian children aged 8 to 12, of whom 270 students were recruited by cluster sampling from six provinces. They complete the Canadian Assessment of Physical Literacy 2 (CAPL-2) and the International Physical Activity Survey. To examine the cultural environment, the components of geographic location (west, south, central, east, and northwest), place of residence (downtown, suburban, and village), and gender (boys and girls) were used. A multivariate ANOVA analysis was used to analyze the data. Results From the geographic location, the findings showed that students inhabit in the west and east of Iran have significantly higher scores than their counterparts living in the central, south, and northwest at PA and PL (P < 0.001). From the place of residence, we observed a higher level of PA and PL in children living in the village than in those living in the suburbs and downtown (P < 0.001). In terms of gender, boys have higher PL and PA scores (P < 0.001). Conclusion The findings demonstrate that socio-cultural factors, geographic location, place of residence, and gender have different impacts on children’s PL and physical activity. Therefore, we suggest using ecologically appropriate decentralized planning in a physical education curriculum

The Effect of Four Weeks of High-intensity Interval Training on PGC-1α and VEGF Protein Contents in Skeletal Muscle of Active Men

Background and Aim: Low-volume, high-intensity interval training (HIT) increase skeletal muscle aerobic capacity, yet little is known about the potential mechanisms in improvement of this adaptability. The purpose of present study was to examine the effect of four weeks of HIT on peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and vascular endothelial growth factor (VEGF) protein contents in skeletal muscle of active men. Materials and Methods: Eight active male students voluntarily and purposefully participated in this study. One week before the experiment started; subjects were familiar with protocol of research. Needle biopsy samples vastus lateralis were obtained 48 h before training and 72 h after the final training session. HIT protocol consisted of 11-15 bouts of 1 min cycling at ∼85-90% of reserve heart rate separated by 1 min of active recovery between each, 3 sessions per week for 4 weeks. Variables were measured by ELISA. All data were analyzed using paired t-test and at the level of significance of p ≤ 0.05. Findings: Results of study showed the four weeks of HIT lead to significant increase in PGC-1α and VEGF (p < 0.001). Conclusion: Our findings suggest that activation of VEGF from PGC-1α pathway is part of cellular-molecular mechanisms of high-intensity interval training. So, probably angiogenesis in skeletal muscle is one of the most important factors in improving of aerobic performance, which requires more studies

Occlusion Training During Specific Futsal Training Improves Aspects of Physiological and Physical Performance

This study aimed to examine the effects of lower limb blood flow restriction (BFR) performed during 3-a-side futsal game training on aerobic and anaerobic performance of futsal players. Twelve male futsal players were randomized into two groups (n = 6); both groups performed ten sessions of the 3-a-side game every other day in half of a futsal court; but one group trained under BFR conditions. Pneumatic cuffs used for the BFR group were inflated to 110% leg systolic blood pressure and increased by 10% after each two completed sessions. Before and after the training sessions subjects completed a series of tests to assess aerobic and anaerobic performances along with changes in blood lactate and anabolic and catabolic hormones. All aerobic and anaerobic performance variables improved in both group after training, however improvements in mean power (12.2%, p = 0.03), run time to fatigue (TTF), (7.1%, p = 0.02) and running economy (RE), (-22.7%, p = 0.01) were significantly greater in the BFR group. There were also significant increases in growth hormone (p = 0.01), testosterone to cortisol ratio at first session (p = 0.01) and rate of lactate removal (p = 0.01) at last session in the BFR group compared to the non-BFR group. Small-sided game (SSG) training with the addition of BFR because of accumulated metabolites and hormonal changed leads to substantially greater increases in performance than SSGs training alone

Multi Directional Repeated Sprint Is a Valid and Reliable Test for Assessment of Junior Handball Players

The aim of the present study was to examine the validity and reliability of a 10 × (6 × 5 m) multi-directional repeated sprint ability test (RSM) in elite young team handball (TH) players. Participants were members of the Iranian national team ( = 20, age 16.4 ± 0.7 years, weight 82.5 ± 5.5 kg, height 184.8 ± 4.6 cm, body fat 15.4 ± 4.3%). The validity of RSM was tested against a 10 × (15 + 15 m) repeated sprint ability test (RSA), Yo-Yo Intermittent Recovery test Level 1 (Yo-Yo IR1), squat jump (SJ) and countermovement jump (CMJ). To test the reliability of RSM, the participants repeated the testing sessions of RSM and RSA 1 week later. Both RSA and RSM tests showed good to excellent reliability of the total time (TT), best time (BT), and weakest time (WT). The results of the correlation analysis showed significant inverse correlations between maximum aerobic capacity and TT in RSA ( = -0.57, ≤ 0.05) and RSM ( = -0.76, ≤ 0.01). There was also a significant inverse correlation between maximum aerobic capacity with fatigue index (FI) in RSA test ( = -0.64, ≤ 0.01) and in RSM test ( = -0.53, ≤ 0.05). BT, WT, and TT of RSA was largely-to-very largely correlated with BT ( = 0.58, ≤ 0.01), WT ( = 0.62, ≤ 0.01), and TT ( = .65, ≤ 0.01) of RSM. BT in RSM was also correlated with FI in RSM ( = 0.88, ≤ 0.01). In conclusion, based on the findings of the current study, the recently developed RSM test is a valid and reliable test and should be utilized for assessment of repeated sprint ability in handball players