Characterization of the Sideritis scardica Extract SidTea+TM and Its Effect on Physiological Profile, Metabolic Health and Redox Biomarkers in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Study.

This study aimed to characterize a Sideritis scardica extract (SidTea+TM) and investigate its effect on the physiological profile, metabolic health and redox status in healthy individuals. The chemical profile and antioxidant potential of the SidTea+TM extract were evaluated by UPLC-HRMS analysis and in vitro cell-free methods. Twenty-eight healthy adults participated in this randomized, double-blind, placebo-controlled study. Participants consumed 1500 mg/day of SidTea+TM or a placebo for 4 weeks. At baseline and post-supplementation, participants were assessed for their anthropometric and physiological profile and provided a resting blood sample. SidTea+TM decreased (p < 0.05) systolic blood pressure (-10.8 mmHg), mean arterial pressure (-4.5 mmHg), resting heart rate (-3.1 bpm) and handgrip strength of the non-dominant limb (-0.8 kg) whereas the placebo decreased (p < 0.05) handgrip strength of the dominant (-5.8 kg) and non-dominant (-3.2 kg) limb. SidTea+TM also resulted in an increase (p < 0.05) in estimated VO2max (+1.1 mL/kg/min) and a reduction (p < 0.05) in γ-GT and SGPT enzymatic activity in serum (-3.7 and -3.3 U/L, respectively). Finally, SidTea+TM increased (p < 0.001) total antioxidant capacity and decreased (p < 0.05) lipid peroxidation levels in plasma. These results indicate that SidTea+TM is a potent and safe to use antioxidant that can elicit positive changes in indices of blood pressure, cardiorespiratory capacity, liver metabolism, and redox status in healthy adults over a 4-week supplementation period.

Recovery During Successive 120-min Football Games: Results from the 120-min Placebo/Carbohydrate Randomized Controlled Trial.

PURPOSE: To examine the recovery kinetics (i.e. time-dependent changes) of performance-related variables between two 120-min male football games performed three days apart with and without carbohydrate (CHO) supplementation. METHODS: 20 male players (20 ± 1 years; body fat: 14.9 ± 5.1%; VO2max: 59.4 ± 3.7 mL•kg-1•min-1) participated in two 120-min football games (G1, G2) according to a randomized, two-trial, repeated measures, cross-over, double-blind design. Participants received carbohydrate/Placebo supplements during recovery between games. Field activity was monitored during the games. Performance testing and blood sampling were performed before, at 90- and 120-min of each game. Muscle biopsies were collected at baseline, 90- and 120-min of G1 and pre-G2. RESULTS: Compared to G1, G2 was associated with reduced total distance (10,870 vs. 10,685 m during 90-min and 3,327 vs. 3,089 m during extra 30-min; p = 0.007-0.038), average (6.7 vs. 6.2 m•s-1 during extra 30-min match-play; p = 0.007) and maximal speed (32.2 vs. 30.2 m•s-1 during 90-min and 29.0 vs. 27.9 m•s-1 during extra 30-min; p < 0.05), accelerations/decelerations (p < 0.05) and mean HR (p < 0.05). Repeated sprint ability (p < 0.001), jumping (p < 0.05) and strength (p < 0.001) performance were compromised before and during G2. Muscle glycogen was not restored at G2-baseline (p = 0.005). Extended game-play reduced lymphocyte, erythrocyte counts, hematocrit, hemoglobin, reduced glutathione (p < 0.05) and increased DOMS, creatine kinase activity, blood glycerol and ammonia (p < 0.05) and protein carbonyls (p < 0.05) before and during G2. Pax7+ (p = 0.004) and MyoD+ cells (p = 0.019) increased at baseline-G2. Carbohydrate supplementation restored performance and glycogen, reduced glycerol and DOMS responses, and increased leukocyte counts and Pax7+ and MyoD+ cells. CONCLUSIONS: Results suggest that extended football games induce a prolonged recovery of performance which may be facilitated by carbohydrate supplementation during a congested game fixture.

Skeletal muscle and erythrocyte redox status is associated with dietary cysteine intake and physical fitness in healthy young physically active men.

PURPOSE: To investigate the association between redox status in erythrocytes and skeletal muscle with dietary nutrient intake and markers of physical fitness and habitual physical activity (PA). METHODS: Forty-five young physically active men were assessed for body composition, dietary nutrient intake, muscle strength, cardiorespiratory capacity and habitual PA. Blood and muscle samples were collected to estimate selected redox biomarkers. Partial correlation analysis was used to evaluate the independent relationship of each factor with redox biomarkers. RESULTS: Dietary cysteine intake was positively correlated (p < 0.001) with both erythrocyte (r = 0.697) and muscle GSH (0.654, p < 0.001), erythrocyte reduced/oxidized glutathione ratio (GSH/GSSG) (r = 0.530, p = 0.001) and glutathione reductase (GR) activity (r = 0.352, p = 0.030) and inversely correlated with erythrocyte protein carbonyls (PC) levels (r = - 0.325; p = 0.046). Knee extensors eccentric peak torque was positively correlated with GR activity (r = 0.355; p = 0.031) while, one-repetition maximum in back squat exercise was positively correlated with erythrocyte GSH/GSSG ratio (r = 0.401; p = 0.014) and inversely correlated with erythrocyte GSSG and PC (r = - 0.441, p = 0.006; r = - 0.413, p = 0.011 respectively). Glutathione peroxidase (GPx) activity was positively correlated with step count (r = 0.520; p < 0.001), light (r = 0.406; p = 0.008), moderate (r = 0.417; p = 0.006), moderate-to-vigorous (r = 0.475; p = 0.001), vigorous (r = 0.352; p = 0.022) and very vigorous (r = 0.326; p = 0.035) PA. Muscle GSSG inversely correlated with light PA (r = - 0.353; p = 0.022). CONCLUSION: These results indicate that dietary cysteine intake may be a critical element for the regulation of glutathione metabolism and redox status in two different tissues pinpointing the independent significance of cysteine for optimal redox regulation. Musculoskeletal fitness and PA levels may be predictors of skeletal muscle, but not erythrocyte, antioxidant capacity. TRIAL REGISTRATION: Registry: ClinicalTrials.gov, identifier: NCT03711838, date of registration: October 19, 2018.

The Effects of Greek Orthodox Christian Fasting during Holy Week on Body Composition and Cardiometabolic Parameters in Overweight Adults.

This study investigated whether Greek Orthodox Christian fasting during Holy Week can change body composition and cardiometabolic parameters in overweight individuals, and whether these changes are maintained one week after fasting cessation (FC). Body composition and physiological and biochemical parameters were measured before, immediately after (n = 23) and one week after FC (subgroup of n = 10). Fasting resulted in decreased body weight, waist circumference, waist-to-hip ratio, body mass index and total body fat, as well as blood glucose, total cholesterol and low-density lipoprotein cholesterol levels. Nutrition analysis showed a decreased protein and saturated fat intake during fasting. FC (n = 10) resulted in a decreased carbohydrate intake and increased protein and cholesterol intake compared to fasting. Fasting resulted in decreased blood glucose, total cholesterol and LDL cholesterol levels but returned to pre-fasting levels after FC. Greek Orthodox Christian fasting during Holy Week is beneficial for body composition and some aspects of cardiometabolic health. However, these favourable changes are not maintained one week following fasting.

HPA-Axis Activity and Nutritional Status Correlation in Individuals with Alcohol Use Disorder.

Impaired activity of the hypothalamic-pituitary-adrenal axis (HPA-axis) is evident in alcohol use disorder (AUD), and may be implicated in various nutritional and metabolic alterations often seen in individuals with this disorder. The present study examined a possible correlation between HPA-axis activity and nutritional status components in individuals with AUD. Fourteen AUD and fourteen non-AUD males participated; anthropometric and body composition measurements were made, and fasting blood samples were analysed for plasma adrenal corticotropic hormone (ACTH), catecholamines, cortisol and beta-endorphin. Nutrient intake was estimated via a three-day diet record. Waist circumference and waist-to-hip ratio were increased in the AUD group. Thiamine and folic intake were lower in AUD group, although only folic acid intake was insufficient in both AUD and non-AUD groups. Increased epinephrine and norepinephrine were also observed in AUD group compared to non-AUD group. No clear correlation between HPA-axis activity and nutritional status components was found. This study showed that nutrient intake, body composition, and HPA-axis activity were different among AUD and non-AUD individuals. More research on the correlation between nutritional status and HPA-axis activity in AUD individuals should be conducted.

Low-Grade Systemic Inflammation Interferes with Anabolic and Catabolic Characteristics of the Aged Human Skeletal Muscle.

Aging is associated with the development of chronic low-grade systemic inflammation (LGSI) characterized by increased circulating levels of proinflammatory cytokines and acute phase proteins such as C-reactive protein (CRP). Collective evidence suggests that elevated levels of inflammatory mediators such as CRP, interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) are correlated with deteriorated skeletal muscle mass and function, though the molecular footprint of this observation in the aged human skeletal muscle remains obscure. Based on animal models showing impaired protein synthesis and enhanced degradation in response to LGSI, we compared here the response of proteolysis- and protein synthesis-related signaling proteins as well as the satellite cell and amino acid transporter protein content between healthy older adults with increased versus physiological blood hs-CRP levels in the fasted (basal) state and after an anabolic stimulus comprised of acute resistance exercise (RE) and protein feeding. Our main findings indicate that older adults with increased hs-CRP levels demonstrate (i) increased proteasome activity, accompanied by increased protein carbonylation and IKKα/ß phosphorylation; (ii) reduced Pax7+ satellite cells; (iii) increased insulin resistance, at the basal state; and (iv) impaired S6 ribosomal protein phosphorylation accompanied by hyperinsulinemia following an acute RE bout combined with protein ingestion. Collectively, these data provide support to the concept that age-related chronic LGSI may upregulate proteasome activity via induction of the NF-κB signaling and protein oxidation and impair the insulin-dependent anabolic potential of human skeletal muscle.

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.

Effect of whey vs. soy protein supplementation on recovery kinetics following speed endurance training in competitive male soccer players: a randomized controlled trial.

BACKGROUND: Soccer-specific speed-endurance training induces short-term neuromuscular fatigue and performance deterioration over a 72-h recovery period, associated with elevated markers of exercise-induced muscle damage. We compared the effects of whey vs. soy protein supplementation on field activity, performance, muscle damage and redox responses following speed-endurance training in soccer players. METHODS: Ten well-trained, male soccer players completed three speed-endurance training trials, receiving whey protein (WP), soy protein (SP) or an isoenergetic placebo (PL; maltodextrin) according to a randomized, double-blind, crossover, repeated-measures design. A pre-loading period was applied in each trial during which protein supplementation was individually adjusted to reach a total protein intake of 1.5 g/kg/day, whereas in PL protein intake was adjusted at 0.8-1 g/kg/day. Following pre-loading, two speed-endurance training sessions (1 and 2) were performed 1 day apart, over a 3-day experimental period. During each session, field activity and heart rate were continuously monitored using global positioning system and heart rate monitors, respectively. Performance (isokinetic strength of knee extensors and flexors, maximal voluntary isometric contraction, speed, repeated sprint ability, countermovement jump), muscle damage (delayed-onset of muscle soreness, creatine kinase activity) and redox status (glutathione, total antioxidant capacity, protein carbonyls) were evaluated at baseline (pre), following pre-loading (post-load), and during recovery from speed-endurance training. RESULTS: High-intensity and high-speed running decreased (P ≤ 0.05) during speed-endurance training in all trials, but WP and SP mitigated this response. Isokinetic strength, maximal voluntary isometric contraction, 30-m speed, repeated sprint ability and countermovement jump performance were similarly deteriorated during recovery following speed-endurance training in all trials (P ≤ 0.05). 10 m speed was impaired at 24 h only in PL. Delayed-onset of muscle soreness, creatine kinase, total antioxidant capacity and protein carbonyls increased and glutathione decreased equally among trials following speed-endurance training (P ≤ 0.05), with SP inducing a faster recovery of protein carbonyls only at 48 h (P ≤ 0.05) compared to WP and PL. CONCLUSIONS: In conclusion, increasing daily protein intake to 1.5 g/kg through ingestion of either whey or soy protein supplements mitigates field performance deterioration during successive speed-endurance training sessions without affecting exercise-induced muscle damage and redox status markers. TRIAL REGISTRATION: Name of the registry: clinicaltrials.gov. TRIAL REGISTRATION: NCT03753321 . Date of registration: 12/10/2018.

Hybrid neuromuscular training promotes musculoskeletal adaptations in inactive overweight and obese women: A training-detraining randomized controlled trial.

This study investigated the effects of a 10-month high-intensity interval-type neuromuscular training programme on musculoskeletal fitness in overweight and obese women. Forty-nine inactive females (36.4 ± 4.4 yrs) were randomly assigned to either a control (N = 21), a training (N = 14, 10 months) or a training-detraining group (N = 14, 5 months training followed by 5 months detraining). Training used progressive loaded fundamental movement patterns with prescribed work-to-rest intervals (1:2, 1:1, 2:1) in a circuit fashion (2-3 rounds). Muscular strength and endurance, flexibility, passive range of motion (PRoM), static balance, functional movement screen (FMS) and bone mass density (BMD) and content (BMC) were measured at pre-, mid-, and post-intervention. Ten months of training induced greater changes than the controls in (i) BMD (+1.9%, p < 0.001) and BMC (+1.5%, p = 0.023) ii) muscular strength (25%-53%, p = 0.001-0.005); iii) muscular endurance (103%-195%, p < 0.001); and iv) mobility (flexibility: 40%, p < 0.001; PRoM [24%-53%, p = 0.001-0.05;]; balance: 175%, p = 0.058; FMS: +58%, p < 0.001). The response rate to training was exceptionally high (86-100%). Five months of detraining reduced but not abolished training-induced adaptations. These results suggest that a hybrid-type exercise approach integrating endurance-based bodyweight drills with resistance-based alternative modes into a real-world gym setting may promote musculoskeletal fitness in overweight and obese women.

HPA axis responses to acute exercise differ in smokers and non-smokers.

Physical exercise has been proposed as an adjunct in addiction treatment, including tobacco cigarette smoking. The physiological and biochemical mechanisms that could be affected by physical exercise in smokers and that could help quit smoking have not been investigated yet. OBJECTIVE: To investigate whether the effects of acute exercise on smoking behavior and HPA axis activation in smokers are intensity-dependent. METHODS: Healthy, non-systematically exercising individuals [25 smokers (age: 33±1.4 years) and 10 non-smokers (age: 34±2.1 years)] underwent three trials [moderate intensity (MI), high intensity (HI) exercise, control (C)] in a counterbalanced order, after an overnight fast and smoking abstinence, separated by at least six days. MI involved cycling at 50-60% of Heart Rate Reserve (HRR) for 30 min, HI involved cycling at 65-75% HRR for 30 min, while in C participants rested for 30 min. Time till the first cigarette following each trial was recorded. Smoking urge was evaluated and blood samples, [analyzed for ß-endorphin (ß-E), adrenocorticotropic hormone (ACTH), cortisol and catecholamines], were obtained prior to and immediately after each trial. RESULTS: ß-E, ACTH, catecholamines and cortisol responses to exercise were intensity-dependent and differed in smokers and non-smokers. Resting ß-E levels were 2-2.5 times lower in smokers compared to non-smokers. HI resulted in increased ß-E levels in both groups, with smokers exhibiting similar levels to that observed in non-smokers. Although smoking urge did not change post-exercise in smokers, time till first cigarette increased following both MI (64.6%) and HI (77.9%) compared to C. CONCLUSIONS: HPA axis activation in response to exercise may differ between smokers and non-smokers. Smokers have lower resting levels of ß-E compared to non-smokers and, since HI exercise increases ß-E to similar levels to those of non-smokers and delays smoking, this may be used as an adjunct in smoking cessation.

Correction: High intensity, circuit-type integrated neuromuscular training alters energy balance and reduces body mass and fat in obese women: A 10-month training-detraining randomized controlled trial.

[This corrects the article DOI: 10.1371/journal.pone.0202390.].

The Effects of Postprandial Resistance Exercise on Blood Glucose and Lipids in Prediabetic, Beta-Thalassemia Major Patients.

Insulin resistance and diabetes mellitus are common consequences of iron overload in the pancreas of beta-thalassemia major (BTM) patients. Moreover, postprandial blood glucose elevations are linked to major vascular complications. The purpose of this study was to investigate the effects of a bout of acute resistance exercise following breakfast consumption of glucose and fat on the metabolism in prediabetic, BTM patients. Six patients underwent two trials (exercise and control) following breakfast consumption (consisting of approximately 50% carbohydrates, 15% proteins, 35% fat), in a counterbalanced order, separated by at least three days. In an exercise trial, patients performed chest and leg presses (3 sets of 10 repetitions maximum/exercise), while in the control trial they rested. Blood samples were obtained in both trials at: pre-meal, 45 min post-meal (pre-exercise/control), post-exercise/control, 1 h post-exercise/control, 2 h post-exercise/control and 24 h post-exercise/control. Blood was analysed for glucose and lipids (total cholesterol, High Density Lipoprotein-cholesterol, Low Density Lipoprotein-cholesterol, triglycerides). Blood glucose levels increased significantly 45 min following breakfast consumption. Blood glucose and lipids did not differ between trials at the same time points. It seems that a single bout of resistance training is not sufficient to improve blood glucose and fat levels for the subsequent 24-h post-exercise period in prediabetic, BTM patients.

High-intensity interval neuromuscular training promotes exercise behavioral regulation, adherence and weight loss in inactive obese women.

It is unclear how high-intensity, interval-type nontraditional exercise training programmes can be feasible and effective options for inactive obese individuals. This randomized controlled trial investigated the hypothesis that a 10-month high-intensity, interval-type neuromuscular training programme (DoIT) with adjunct portable modalities, performed in a small-group setting, induces improvements in psychological well-being, subjective vitality and exercise behavioural regulations in obese women. Associations between adherence, psychological and physiological indicators were also investigated. Forty-nine previously inactive obese females (36.4 ± 4.4 yrs) were randomly assigned to three groups (control; N = 21, 10-month training; N = 14, or 5-month training plus 5 month-detraining; N = 14). DoIT was a supervised, progressive, and time-efficient (<30 min) programme that used 10-12 functional/neuromotor exercises and prescribed work and rest time intervals (20-40 sec) in a circuit fashion (1-3 rounds) for 10 months. Questionnaires were used to measure psychological distress, subjective vitality, and behavioural regulations in exercise at pre-, mid-, and post-intervention. The 10-month training reduced psychological distress (72%, p = 0.001), external regulation (75%, p = 0.011) and increased vitality (53%, p = 0.001), introjected regulation (63%, p = 0.001), intrinsic regulation (33%, p = 0.004), and identified regulation (88%, p = 0.001). A moderate to strong positive relationship was found between adherence rate and identified regulation scores (r = 0.59, p = 0.001) and between VO2peak and identified regulation scores (r = 0.59, p = 0.001). A mild dissociation between exercise intensity and perceived exertion was also observed. Our novel findings suggest that a 10-month implementation of a high-intensity interval neuromuscular training programme promotes positive psychological adaptations provoking exercise behavioural regulation and adherence while inducing weight loss in inactive obese women.

Exercise-Induced Regulation of Redox Status in Cardiovascular Diseases: The Role of Exercise Training and Detraining.

Although low levels of reactive oxygen species (ROS) are beneficial for the organism ensuring normal cell and vascular function, the overproduction of ROS and increased oxidative stress levels play a significant role in the onset and progression of cardiovascular diseases (CVDs). This paper aims at providing a thorough review of the available literature investigating the effects of acute and chronic exercise training and detraining on redox regulation, in the context of CVDs. An acute bout of either cardiovascular or resistance exercise training induces a transient oxidative stress and inflammatory response accompanied by reduced antioxidant capacity and enhanced oxidative damage. There is evidence showing that these responses to exercise are proportional to exercise intensity and inversely related to an individual's physical conditioning status. However, when chronically performed, both types of exercise amplify the antioxidant defense mechanism, reduce oxidative stress and preserve redox status. On the other hand, detraining results in maladaptations within a time-frame that depends on the exercise training intensity and mode, as high-intensity training is superior to low-intensity and resistance training is superior to cardiovascular training in preserving exercise-induced adaptations during detraining periods. Collectively, these findings suggest that exercise training, either cardiovascular or resistance or even a combination of them, is a promising, safe and efficient tool in the prevention and treatment of CVDs.

The redox-dependent regulation of satellite cells following aseptic muscle trauma (SpEED): study protocol for a randomized controlled trial.

BACKGROUND: Muscle satellite cells (SCs) are crucial for muscle regeneration following muscle trauma. Acute skeletal muscle damage results in inflammation and the production of reactive oxygen species (ROS) which may be implicated in SCs activation. Protection of these cells from oxidative damage is essential to ensure sufficient muscle regeneration. The aim of this study is to determine whether SCs activity under conditions of aseptic skeletal muscle trauma induced by exercise is redox-dependent. METHODS/DESIGN: Based on the SCs content in their vastus lateralis skeletal muscle, participants will be classified as either high or low respondents. In a randomized, double-blind, crossover, repeated-measures design, participants will then receive either placebo or N-acetylcysteine (alters redox potential in muscle) during a preliminary 7-day loading phase, and for eight consecutive days following a single bout of intense muscle-damaging exercise. In both trials, blood samples and muscle biopsies will be collected, and muscle performance and soreness will be measured at baseline, pre-exercise, 2 and 8 days post exercise. Biological samples will be analyzed for redox status and SCs activity. Between trials, a 4-week washout period will be implemented. DISCUSSION: This study is designed to investigate the impact of redox status on SCs mobilization and thus skeletal muscle potential for regeneration under conditions of aseptic inflammation induced by exercise. Findings of this trial should provide insight into (1) molecular pathways involved in SCs recruitment and muscle healing under conditions of aseptic skeletal muscle trauma present in numerous catabolic conditions and (2) whether skeletal muscle's potential for regeneration depends on its basal SCs content. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03711838 . Registered on 19 Oct 2018.

Protein-Based Supplementation to Enhance Recovery in Team Sports: What is the Evidence?

Protein supplementation is a major nutritional practice among professional and amateur team-sport athletes representing a market of $5 billion in the USA alone. This practice, however, may not be supported by evidence-based science. Our objective as to present a thorough review of literature investigating the effects of protein supplementation on performance recovery and exercise-induced muscle damage following team-sport activity. PubMed-derived, full English language articles investigating the effects of protein-based supplementation/feeding on skeletal muscle performance, muscle damage and inflammatory status during recovery following team-sport activity were included. Studies investigated professional or amateur team-sport athletes participating in regular training and competition as well as examining the impact of protein supplementation on performance, muscle damage/soreness and inflammatory markers after team-sport activity. Finally, ten articles (150 participants) met the inclusion criteria. Experimental designs were evaluated for confounders. All protocols employing team-sport activity increased systemic muscle damage indicators and inflammatory markers and deteriorated performance during recovery. Protein-based supplementation attenuated the rise in muscle damage markers and enhanced performance recovery in six (60% of the studies included) and three (30% of the studies included) out of 10 studies, respectively. In contrast, immunity and muscle soreness remained unaffected by protein ingestion, independent of dosage and distribution pattern. In conclusion, there are limited and inconsistent data showing that protein supplementation may enhance performance recovery following team-sport activity despite an attenuation of indirect markers of muscle damage. Interpretation of results is limited by small sample sizes, high variability in tested supplements, participants' training level, length of recovery periods, absence of direct measurement of myofibrillar disruption, protein turnover and protein metabolism, and lack of dietary monitoring during experimentation.

Dose-response effects of high-intensity interval neuromuscular exercise training on weight loss, performance, health and quality of life in inactive obese adults: Study rationale, design and methods of the DoIT trial.

Obesity is associated with high mortality and morbidity rates and low levels of quality of life among adults globally. It is critical to examine evidence-based practices for developing lifestyle behavioral changes such as physical movement and structured exercise training. The DoIT protocol, a high-intensity interval exercise training (HIIT) program, effectively reduces body mass, alters energy balance, and improves performance of obese adults with a high adherence rate. This study aims to determine the dose-response effects of the DoIT protocol on body composition, health, performance and quality of life in sedentary obese adults. This study will recruit 88 sedentary, obese males and females (BMI 25.0-34.9; 30-50 years) who will be randomly assigned to one of four groups: (i) control (n = 22), (ii) one session/week (n = 22), (iii) two sessions/week (n = 22) or (iv) three sessions/week (n = 22). DoIT will use a supervised, circuit-type (1-3 rounds), functional/neuromotor and progressive exercise program for 12 months. DoIT incorporates 8-12 multi-planar, fundamental and complex, whole body movements and uses bodyweight and alternative exercise modes as a resistance. DoIT utilizes prescribed work-to-rest ratios which will be varied every four weeks. Each session will last less than 30 min. DoIT will be implemented for a year and its effects on body mass and body composition, physical fitness, functional capacity, bone health, leptin, adiponectin, blood lipids, glycemic control, inflammation, oxidative stress and quality of life will be assessed. The outcomes of the proposed study will provide insight on optimal exercise prescription guidelines for such HIIT-type exercise protocols for overweight or obese individuals.

Exercise in Glucose-6-Phosphate Dehydrogenase Deficiency: Harmful or Harmless? A Narrative Review.

OBJECTIVES: Glucose-6-phosphate dehydrogenase (G6PD) deficiency, theoretically, renders red blood cells (RBC) susceptible to oxidative stress. G6PD deficiency has also been found in other types of cells than RBC, such as leukocytes and myocytes, where an inefficient protection against oxidative stress may occur too. Glutathione (GSH), a significant antioxidant molecule, levels are lower in G6PD individuals, and theoretically, the probability of oxidative stress and haemolysis due to exercise in individuals with G6PD deficiency is increased, whereas dietary supplementation with antioxidants may have beneficial effects on various aspects of this enzymopathy. METHODS: A search of the available literature was conducted using the keywords glucose-6-phosphate dehydrogenase (G6PD), deficiency, disease, exercise, muscle, antioxidant, vitamin, supplement, and supplementation. The search was limited to publications in English, conducted on humans, and published until August 2018. After screening, only relevant articles were included. RESULTS: There is little evidence indicating that G6PD deficiency can cause perturbations in redox status, haemolysis, and clinical symptoms such as fatigability and myoglobinuria, especially after intense exercise, compared to individuals with normal enzyme levels. CONCLUSIONS: Exercise could be used by G6PD-deficient individuals as a tool to improve their quality of life. However, there is a lack of training studies, and assessment of the effects of regular and systematic exercise in G6PD-deficient individuals is warranted. Finally, since GSH levels are lower in G6PD deficiency, it would be interesting to examine the effects of antioxidant or cysteine donor supplements on redox status after exercise in these individuals.

Exercise and Redox Status Responses Following Alpha-Lipoic Acid Supplementation in G6PD Deficient Individuals.

G6PD deficiency renders cells more susceptible to oxidative insults, while antioxidant dietary supplementation could restore redox balance and ameliorate exercise-induced oxidative stress. To examine the effects of alpha-lipoic acid (ALA) supplementation on redox status indices in G6PD deficient individuals, eight male adults with G6PD deficiency (D) participated in this randomized double-blind placebo-controlled crossover trial. Participants were randomly assigned to receive ALA (600 mg/day) or placebo for 4 weeks separated by a 4-week washout period. Before and at the end of each treatment period, participants exercised following an exhaustive treadmill exercise protocol. Blood samples were obtained before (at rest), immediately after and 1h after exercise for later analysis of total antioxidant capacity (TAC), uric acid, bilirubin, thiobarbituric acid reactive substances (TBARS) and protein carbonyls (PC). ALA resulted in significantly increased resting TAC and bilirubin concentrations. Moreover, TAC increased immediately and 1h after exercise following both treatment periods, whereas bilirubin increased immediately after and 1h after exercise following only ALA. No significant change in uric acid, TBARS or PC was observed at any time point. ALA supplementation for 4 weeks may enhance antioxidant status in G6PD individuals; however, it does not affect redox responses to acute exercise until exhaustion or exercise performance.

The Effects of Acute Low-Volume HIIT and Aerobic Exercise on Leukocyte Count and Redox Status.

A single bout of exercise can result in inflammatory responses, increased oxidative stress and upregulation of enzymatic antioxidant mechanisms. Although low-volume high-intensity interval training (HIIT) has become popular, its acute responses on the above mechanisms have not been adequately studied. The present study evaluated the effects of HIIT on hematological profile and redox status compared with those following traditional continuous aerobic exercise (CET). Twelve healthy young men participated in a randomized crossover design under HIIT and CET. In HIIT session, participants performed four 30-sec sprints on a cycle-ergometer with 4 min of recovery against a resistance of 0.375 kg/kg of body mass. CET consisted of 30-min cycling on a cycle-ergometer at 70% of their VO2max. Blood was drawn at baseline, immediately post, 24h, 48h and 72h post-exercise and was analyzed for complete blood count and redox status (thiobarbituric acid reactive substances, [TBARS]; protein carbonyls, [PC]; total antioxidant capacity, [TAC]; catalase and uric acid). White blood cells (WBC) increased after both exercise protocols immediately post-exercise (HIIT: 50% and CET: 31%, respectively). HIIT increased (+22%) PC post-exercise compared to baseline and CET (p < 0.05). HIIT increased TAC immediately post-exercise (16%) and at 24h post-exercise (11%, p < 0.05), while CET increased TAC only post-exercise (12%, p < 0.05) compared to baseline, and TAC was higher following HIIT compared to CET (p < 0.05). Both HIIT and CET increased uric acid immediately post- (21% and 5%, respectively, p < 0.05) and 24h (27% and 5%, respectively, p < 0.05) post-exercise and the rise was greater following HIIT (p < 0.05). There were no significant changes (p > 0.05) for TBARS and catalase following either exercise protocol. Low-volume HIIT is associated with a greater acute phase leukocyte count and redox response than low-volume CET, and this should be considered when an exercise training program is developed and complete blood count is performed for health purposes.