Effect of training and crocin supplementation on mitochondrial biogenesis and redox-sensitive transcription factors in liver tissue of type 2 diabetic rats

Present study investigated the effect of continued training (CT) and interval training (IT) with crocin (C) supplementation on mitochondrial biogenesis and redox-sensitive transcription factors in liver tissue of type 2 diabetes (T2D) rats. Forty-eight high fat diet and streptozotocin- induced diabetic rats (mean age: 20 weeks, mean weight: 360.12 ± 12.11 g) were randomly divided into six groups including: (1) sham (Sh), (2) CT, (3) IT, (4) C (25 mg/kg/day), (5) CT + C, and (6) IT + C. IT and CT were performed 8 weeks for five sessions per week on treadmill with 80-85% and 50-55% of maximum speed running respectively. IT, CT and C decreased AP1 and increased LCAD (p ≤ .05); C increased SIRT1 (p ≤ .05); IT + C and CT + C decreased AP1 as well as increased NF-κB and LCAD (p ≤ .05); IT + C increased SIRT1, SIRST3 and PGC1-α (p ≤ .05). It appears that IT along with C compared to CT and C have favourable effect on mitochondrial biogenesis factors.

Hybrid Neuromuscular Training Improves Cardiometabolic Health and Alters Redox Status in Inactive Overweight and Obese Women: A Randomized Controlled Trial

This randomized controlled trial investigated the effects of a 5-month high-intensity hybrid-type neuromuscular training program with nontraditional implements on cardiometabolic health, redox status, and cardiovascular disease (CVD) risk in inactive overweight and obese women. Forty-nine inactive female participants with overweight and obesity (age: 36.4 ± 4.4 years; BMI: 29.1 ± 2.9 kg/m2) were randomly assigned to either a control (C, n = 21) or a training group (TR, n = 28). TR followed a 20-week supervised, progressive, time-efficient (3 days/week; 6-15 min net exercise time) program implementing loaded fundamental movement patterns with prescribed work-to-rest time intervals (20-40 s, 1:2, 1:1, 2:1) in a circuit fashion (2-3 rounds). Cardiometabolic risk factors were measured at baseline and post-training as secondary outcomes of a larger randomized controlled trial. At post-intervention, TR demonstrated favorable changes in resting heart rate (-7%, p = 0.043), high-density lipoprotein (+18.1%, p = 0.029), atherogenic index (-17%, p = 0.045), mean arterial pressure (-4.5%, p = 0.03), waist circumference (-6.2%, p = 0.005), waist-to-hip ratio (-4.6%; p = 0.015), metabolic syndrome severity score (-222%, p = 0.024), full 30-year CVD risk (-15.8%, p = 0.002) and hard 30-year CVD risk (-17.6%, p = 0.01), vascular age (-7.8%, p = 0.002), protein carbonyls (-45.7%, p = 0.001), catalase activity (+15.2%, p = 0.023), and total antioxidant capacity (+11.4%, p = 0.002) relative to C. Additionally, TR induced beneficial changes in fasting glucose (-3.4%, p = 0.002), homeostatic model assessment for insulin resistance (-15.7%, p < 0.001), diastolic blood pressure (-5.6%, p < 0.001), reduced glutathione (+39.8%, p < 0.001), 10-year CVD risk (-17.4%, p = 0.011), and total bilirubin (-21.7%, p < 0.001) compared to baseline. These results suggest that hybrid-type neuromuscular training may improve aspects of cardiometabolic health and antioxidant status in inactive overweight and obese women providing a time-efficient (~100 min/week) exercise approach in a real-world gym setting.

Acute and delayed hormonal and blood cell count responses to high-intensity exercise before and after short-term high-intensity interval training

The acute and delayed hormonal and blood cell responses to a high-intensity interval training (HIIT) session, were examined before and after a 3-week intervention (9 HIIT sessions of 4-6 × 30 s high-intensity cycling bouts) in eight recreationally active male volunteers (age: 24.3 ± 1.4 y, VO₂max: 41.2 ± 3.2 ml/kg/min). Blood samples were collected before and 0.5, 24, 48 h following the first and last training session. Before training, the HIIT session induced acute increases in cortisol, prolactin and TSH concentration, while free-T4 peaked 24 h later (p < 0.001) and testosterone remained unchanged. White blood cell count was increased 0.5 h after exercise (p < 0.001), while lymphocyte percentage decreased 24 h post exercise (p < 0.01). After three weeks of HIIT, cortisol, WBC and lymphocyte responses were decreased by ~42% (p = 0.002), 8.6% (p = 0.032) and 9.6% (p = 0.039), respectively, despite an increase in total work. These findings show that short-term HIIT may induce rapid adaptations of the hypothalamic-pituitary-adrenal axis and may blunt exercise-induced immune responses.

Effect of high intensity interval training on body composition in women before and after menopause: a meta-analysis

NEW FINDINGS

What is the topic of this review? A meta-analysis of the efficacy of high intensity interval training (HIIT) in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. What advances does it highlight? HIIT programmes in women significantly decrease body weight and total and abdominal FM. Their effects are more evident in pre- than in postmenopausal women. Cycling HIIT seems more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions a week should be promoted.

ABSTRACT

High-intensity interval training (HIIT) is a stimulating modality for reducing body weight and adipose tissue. The purpose of this meta-analysis was to assess the efficacy of HIIT in reducing weight, total fat mass (FM) and (intra)-abdominal FM in normal-weight and overweight/obese women before and after menopause. A structured electronic search was performed to find all publications relevant to our review. Stratified analyses were made of hormonal status (pre- vs. postmenopausal state), weight, HIIT modalities (cycling vs. running), programme duration (< or ≥8 weeks) and the methods used to measure body composition (dual-energy X-ray absorptiometry vs. computed tomography, Magnetic Resonance Imaging and others). A total of 38 studies involving 959 subjects were included. Our meta-analysis showed that overall HIIT programmes significantly decrease weight, total and abdominal FM in women. Both normal weight and overweight/obese women lost total FM after HIIT protocols whereas HIIT was only effective in decreasing abdominal FM in women with excess adiposity. When pre- and postmenopausal women were considered separately, the effect of HIIT on weight, total and abdominal FM were only significant before menopause. Cycling HIIT seemed more effective than running, especially in postmenopausal women, and training interventions longer than 8 weeks comprising three sessions were more efficient. HIIT is a successful strategy to lose weight and FM in normal weight and overweight/obese women. However, further studies are still needed to draw meaningful conclusions about the real effectiveness of HIIT protocols in postmenopausal women.