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Vitamin D supplementation and exercise for improving physical function, body composition and metabolic health in overweight or obese older adults with vitamin D deficiency: a pilot randomized, double-blind, placebo-controlled trial.
Mesinovic, J, Rodriguez, AJ, Cervo, MM, Gandham, A, Xu, CLH, Glavas, C, de Courten, B, Zengin, A, Ebeling, PR, Scott, D
European journal of nutrition. 2023;62(2):951-964
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Overweight and obese older adults are at increased risk for vitamin D deficiency, which is associated with poor metabolic and musculoskeletal health, unfavourable body composition, and attenuated responses to exercise. The aim of this study was to determine whether, compared with placebo, vitamin D3 supplementation (4000 IU/day) taken prior to and during a 12-week exercise program improves physical function, body composition or metabolic health, in overweight or obese older adults with vitamin D deficiency. This study is a 24-week parallel-group, double-blind, placebo-controlled pilot randomised controlled trial. Fifty overweight or obese participants were enrolled for the study, and randomised to either 4000 IU/day of oral vitamin D3 or identical placebo. Results demonstrated that 4000 IU/day vitamin D3 supplementation: - did not affect gait speed when taken with or without exercise, - helped achieve optimal serum 25-hydroxyvitamin D levels and decreased waist circumference (compared with placebo) following multi-modal exercise. - taken alone without exercise reduced stair climb times. However, vitamin D3 supplementation did not have any beneficial effects on other biochemical, body composition or physical function parameters when taken alone or during exercise. Authors conclude that future studies should focus on populations with moderate or severe vitamin D deficiency as they are more likely to experience therapeutic benefits from vitamin D supplementation.
Abstract
PURPOSE Vitamin D supplementation may have non-skeletal health benefits and enhance exercise responsiveness, particularly in those with low vitamin D levels. We determined whether, compared with placebo, vitamin D supplementation taken prior to and during a 12-week exercise program improves physical function, body composition or metabolic health, in overweight and obese older adults with vitamin D deficiency. METHODS Fifty overweight or obese older adults (mean ± SD age: 60 ± 6 years; BMI 30.6 ± 5.7 kg/m2) with vitamin D deficiency (25-hydroxyvitamin D [25(OH)D] < 50 nmol/L) were recruited. Participants were randomly allocated to receive either vitamin D3 (4000 IU/day) or matching placebo for 24 weeks. Between weeks 12 and 24, all participants completed multi-modal exercise three days per week while continuing with vitamin D/placebo. Mean changes in physical function (primary outcome: gait speed), body composition and biochemical parameters at weeks 12 and 24 were compared between groups. RESULTS Vitamin D supplementation, with or without exercise, had no effect on gait speed. From baseline to week 12, vitamin D supplementation increased serum 25(OH)D levels (placebo: 2.5 ± 14.7 nmol/L; treatment: 43.4 ± 18.4 nmol/L; P < 0.001) and reduced stair climb times (placebo: 0.3 ± 1.0 s; treatment: - 0.2 ± 1.0 s; P = 0.046). From 12 to 24 weeks, vitamin D supplementation combined with exercise decreased waist circumference (placebo: 1.3 ± 7.3 cm; treatment: - 3.0 ± 6.1 cm; P = 0.02) and waist-to-hip ratio (placebo: 0.01 ± 0.05; treatment: - 0.03 ± 0.05; P = 0.01) relative to placebo. Vitamin D supplementation, with or without exercise, had no effect on other physical function, body composition or metabolic health outcomes. CONCLUSION Vitamin D supplementation had no effect on most physical function, body composition or metabolic health parameters when taken alone, or during exercise, in overweight or obese older adults with vitamin D deficiency. Vitamin D-related improvements in stair climb times and waist circumference suggest that future trials should explore the effects of vitamin D on muscle power, and its effects on body composition when combined with exercise, in populations with moderate or severe vitamin D deficiency.
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Effects of Morning Vs. Evening exercise on appetite, energy intake, performance and metabolism, in lean males and females.
Mode, WJA, Slater, T, Pinkney, MG, Hough, J, James, RM, Varley, I, James, LJ, Clayton, DJ
Appetite. 2023;182:106422
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Long-term weight management is notoriously difficult, with many people experiencing progressive weight gain throughout adult life. The aim of this study was to assess the acute effects of morning and evening cycling exercise on appetite, post-exercise ad-libitum energy intake, substrate metabolism, voluntary performance, and subjective responses to exercise, in young, healthy males and females. Sixteen healthy participants (eight males and eight females) were recruited to the study. Each participant completed two preliminary trials, followed by two experimental trials which involved exercising at 10:30 or 18:30. Results show that: - post-exercise energy intake was greater after acute cycling exercise performed in the evening compared to the morning, despite no post-exercise differences in subjective appetite. - there wasn’t any difference in exercise performance between morning and evening exercise. - exercise timing did not affect performance during a 15-min all-out performance test. Authors conclude that their findings demonstrate a disconnect between subjective appetite and ad-libitum energy intake but provide some evidence that exercise can offset circadian-related appetite profiles.
Abstract
Exercise is an important component of a weight management strategy. However, little is known about whether circadian variations in physiological and behavioural processes can influence the appetite and energy balance responses to exercise performed at different times of the day. This study compared the effects of morning and evening exercise on appetite, post-exercise energy intake, and voluntary performance. In randomised, counterbalanced order, 16 healthy males and females (n = 8 each) completed two trials, performing morning exercise at 10:30 (AMEx) or evening exercise at 18:30 (PMEx). Exercise consisted of 30 min steady-state cycling (60% V˙ O2peak), and a 15-min performance test. A standardised meal (543 ± 86 kcal) was consumed 2-h before exercise and ad-libitum energy intake was assessed 15 min after exercise, with subjective appetite measured throughout. Absolute ad-libitum energy intake was 152 ± 126 kcal greater during PMEx (P < 0.001), but there was no differences in subjective appetite between trials immediately pre-exercise, or immediately before the post-exercise meal (P ≥ 0.060). Resting energy expenditure (P < 0.01) and carbohydrate oxidation (P < 0.05) were greater during AMEx, but there were no differences in substrate oxidation or energy expenditure during exercise (P ≥ 0.155). Exercise performance was not different between trials (P = 0.628). In conclusion, acute morning and evening exercise prompt similar appetite responses, but post-exercise ad-libitum energy intake is greater following evening exercise. These findings demonstrate discordant responses between subjective appetite and ad-libitum energy intake but suggest that exercise might offset circadian variations in appetite. Longer-term studies are required to determine how exercise timing affects adherence and weight management outcomes to exercise interventions. TRIAL REGISTRATION NCT04742530, February 8, 2021.
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Resistance Exercise Training Increases Muscle Mass and Strength in Prostate Cancer Patients on Androgen Deprivation Therapy.
Houben, LHP, Overkamp, M, VAN Kraaij, P, Trommelen, J, VAN Roermund, JGH, DE Vries, P, DE Laet, K, VAN DER Meer, S, Mikkelsen, UR, Verdijk, LB, et al
Medicine and science in sports and exercise. 2023;55(4):614-624
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Androgen deprivation therapy (ADT) forms the cornerstone in the treatment of localised high-risk, locally advanced, and metastatic prostate cancer (PCa). The hypothesis of this study was that protein supplementation augments the benefits of prolonged resistance exercise training to attenuate the decline in muscle mass, reduce fat mass accrual, and increase strength and physical performance in PCa patients on ADT. This study is a multicentre partly randomised controlled trial, comparing two intervention groups with a separately recruited control group. One hundred and twenty-six patients were included, and ninety-six patients finished the study. Results show that 20 week of resistance exercise training was feasible, safe, and well tolerated, and effectively counteracted the negative effect of ADT treatment on body composition, muscle mass, leg strength, and aerobic capacity in men with advanced PCa. Protein supplementation did not further augment the benefits of resistance exercise training. Authors conclude that protein supplementation is not required to further augment gains in muscle mass and strength after resistance exercise training in PCa patients who habitually consume ample protein.
Abstract
PURPOSE This study aimed to assess the effects of 20 wk resistance exercise training with or without protein supplementation on body composition, muscle mass, muscle strength, physical performance, and aerobic capacity in prostate cancer patients receiving androgen deprivation therapy (ADT). METHODS Sixty prostate cancer patients receiving ADT were randomly assigned to perform 20 wk of resistance exercise training with supplementation of 31 g whey protein (EX + PRO, n = 30) or placebo (EX + PLA, n = 30), consumed immediately after exercise and every night before sleep. A separate control group (CON, n = 36) only received usual care. At baseline and after 20 wk, body composition (dual-energy x-ray absorptiometry), muscle mass (computed tomography scan), muscle strength (1-repetition maximum strength tests), physical performance (Timed Up and Go Test, 30-Second Chair Stand Test, and Stair Climb Test), aerobic capacity (cardiopulmonary exercise test), and habitual dietary intake (food diary) were assessed. Data were analyzed using a two-factor repeated-measures ANOVA. RESULTS Over time, muscle mass and strength increased in EX + PRO and EX + PLA and decreased in CON. Total fat mass and fat percentage increased in EX + PRO and CON, but not in EX + PLA. Physical performance did not significantly change over time in either group. Aerobic capacity was maintained in EX + PLA, but it decreased in EX + PRO and CON. Habitual protein intake (without supplements) averaged >1.0 g·kg body weight -1 ·d -1 , with no differences over time or between groups. CONCLUSIONS In prostate cancer patients, resistance exercise training counteracts the adverse effects of ADT on body composition, muscle mass, muscle strength, and aerobic capacity, with no additional benefits of protein supplementation.
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The impact of Dietary Weight loss, Aerobic Exercise, and Daylong Movement on Social Cognitive Mediators of Long-term Weight loss.
Fanning, J, Nicklas, B, Furlipa, J, Rejeski, WJ
Journal of behavioral medicine. 2023;46(3):499-508
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Obesity in older adults predisposes individuals to physical disability, a host of chronic diseases, and premature mortality. A strong body of evidence indicates that well-designed structured exercise interventions increase older adults’ self-efficacy and satisfaction with their physical functioning, and these are important social cognitive outcomes closely linked with quality of life and health behaviour change. The main aim of this study was to investigate changes in walking self-efficacy and satisfaction after the 6-month intensive phase of the intervention. This study was a secondary analysis of the Empowered with Movement to Prevent Obesity and Weight Regain (EMPOWER) study, which was an 18-month, three-group, single-blind randomised trial. A total of 183 participants were randomly assigned to one of the three treatment arms: weight loss + structured exercise (WL+EX), WL+ sitting less and moving more across the day (SL), or WL+EX+SL. Results showed that: - participants demonstrated improvements in self-efficacy and satisfaction following the 6-month intervention weight loss and physical activity intervention. - participants who received an exercise intervention focused on sustained walking demonstrated significantly better self-efficacy for walking relative to those who did not (WL+SL). - both WL+EX and WL+EX+SL regressed to baseline levels of self-efficacy for walking by month 18, only WL+SL did not significantly decrease self-efficacy scores, sustaining a significant increase over baseline. Authors conclude that programs focused on daylong movement may contribute to improved self-efficacy and satisfaction. Thus, health promotion professionals should demonstrate flexibility in the ways in which physical activity is prescribed for older adults since not everyone resonates with traditional structured exercise.
Abstract
This report contrasts the impact of a dietary weight loss intervention (WL) paired with aerobic exercise (EX) and/or sitting less and moving throughout the day (SL) on self-efficacy for walking (hereafter walking self-efficacy) and satisfaction with physical functioning (hereafter satisfaction). Additional analyses examined dose-response associations between change in weight and changes in these key outcomes. Older adults (N = 112; age = 70.21[Formula: see text]4.43) were randomized to 6 months of WL+EX, WL+SL, or WL+EX+SL followed by a 12-month maintenance period. All groups reported increases in walking self-efficacy at month 6 with greater improvements in WL+EX and WL + EX+SL. Only WL+SL demonstrated improved walking self-efficacy at month 18. All conditions demonstrated improved satisfaction scores at both time points. Changes in walking self-efficacy and satisfaction were negatively associated with change in weight over the 6-month intervention and after the maintenance period. These results support the utility of WL + SL for improving key social cognitive outcomes in aging.
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Effects of a 2-year exercise training on neuromuscular system health in older individuals with low muscle function.
Monti, E, Tagliaferri, S, Zampieri, S, Sarto, F, Sirago, G, Franchi, MV, Ticinesi, A, Longobucco, Y, Adorni, E, Lauretani, F, et al
Journal of cachexia, sarcopenia and muscle. 2023;14(2):794-804
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Ageing is accompanied by a progressive decline in muscle mass and functionality, associated with an increased likelihood of adverse outcomes including falls, fractures, physical disability and mortality, possibly leading to a clinical syndrome known as sarcopenia. Among the causes of sarcopenia, motoneuron and neuromuscular junction (NMJ) degeneration have been proposed as key determinants. The aim of this study was to investigate the effects of a 2-year multimodal training intervention involving aerobic, strength and balance exercises on muscle mass and function, motoneuronal and NMJ health in a population of older individuals classified as sarcopenic. This study was a randomised controlled trial which enrolled 45 sarcopenic participants (34 females and 11 males) who were randomly assigned to one of the two groups: intervention or control group. Results show that the 2-year multimodal training intervention seemingly preserved NMJ stability, preventing serum C-terminal agrin fragment (CAF) [a biomarker of muscle wasting and weakness] concentration rise in the intervention group, although this biomarker increased significantly only in the control group. Conversely, neurofilament light chain (NfL) [clinical biomarker of many neurodegenerative diseases] concentration did not change in either group. Finally, improvements of physical performance were correlated with changes of serum biomarkers of NMJ stability. Authors conclude that a 2-year multimodal training intervention including aerobic, strength and balance exercises is effective for preventing CAF concentration increments, suggesting a positive effect on NMJ stability.
Abstract
BACKGROUND Ageing is accompanied by a progressive loss of skeletal muscle mass and strength, potentially determining the insurgence of sarcopenia. Evidence suggests that motoneuron and neuromuscular junction (NMJ) degeneration contribute to sarcopenia pathogenesis. Seeking for strategies able to slow down sarcopenia insurgence and progression, we investigated whether a 2-year mixed-model training involving aerobic, strength and balance exercises would be effective for improving or preserving motoneuronal health and NMJ stability, together with muscle mass, strength and functionality in an old, sarcopenic population. METHODS Forty-five sarcopenic elderly (34 females; 11 males) with low dual-energy X-ray absorptiometry (DXA) lean mass and Short Physical Performance Battery (SPPB) score <9 were randomly assigned to either a control group [Healthy Aging Lifestyle Education (HALE), n = 21] or an intervention group [MultiComponent Intervention (MCI), n = 24]. MCI trained three times per week for 2 years with a mix of aerobic, strength and balance exercises matched with nutritional advice. Before and after the intervention, ultrasound scans of the vastus lateralis (VL), SPPB and a blood sample were obtained. VL architecture [pennation angle (PA) and fascicle length (Lf)] and cross-sectional area (CSA) were measured. As biomarkers of neuronal health and NMJ stability status, neurofilament light chain (NfL) and C-terminal agrin fragment (CAF) concentrations were measured in serum. Differences in ultrasound parameters, NfL and CAF concentration and physical performance between baseline and follow-up were tested with mixed ANOVA or Wilcoxon test. The relationship between changes in physical performance and NfL or CAF concentration was assessed through correlation analyses. RESULTS At follow-up, MCI showed preserved VL architecture (PA, Lf) despite a reduced CSA (-8.4%, P < 0.001), accompanied by maintained CAF concentration and ameliorated overall SPPB performance (P = 0.007). Conversely, HALE showed 12.7% decrease in muscle CSA (P < 0.001), together with 5.1% and 5.5% reduction in PA and Lf (P < 0.001 and P = 0.001, respectively), and a 6.2% increase in CAF (P = 0.009) but improved SPPB balance score (P = 0.007). NfL concentration did not change in either group. In the population, negative correlations between changes in CAF concentration and SPPB total score were found (P = 0.047), whereas no correlation between NfL and SPPB variations was observed. CONCLUSIONS The present findings suggest that our 2-year mixed aerobic, strength and balance training seemed effective for preventing the age and sarcopenia-related increases in CAF concentration, preserving NMJ stability as well as muscle structure (PA and Lf) and improving physical performance in sarcopenic older individuals.
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Effects of Whey Protein Supplement on 4-Week Resistance Exercise-Induced Improvements in Muscle Mass and Isokinetic Muscular Function under Dietary Control.
Kim, CB, Park, JH, Park, HS, Kim, HJ, Park, JJ
Nutrients. 2023;15(4)
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The popularity of dietary supplements has steadily increased. Among dietary supplements, carbohydrate supplementation is the main source of energy for muscle contraction, whereas amino acid supplementation not only provides energy but also affects muscle protein synthesis and muscle recovery after resistance exercise. The aim of this study was to investigate the effect of whey protein supplementation on changes in muscle mass and isokinetic muscle function following resistance exercise while controlling the participants’ normal diet by providing three meals a day during the entire study period This study was a randomised, double-blind, placebo-controlled trial which recruited thirty-six men in their 20s and 30s. Participants were randomly assigned (1:1) to a whey protein supplement intake group (PSG) and a placebo intake group (CON). Results show that after four weeks of resistance exercise: - the change in muscle mass was significantly different between the two groups. The PSG showed significantly increased muscle mass, whereas the CON did not. - changes in body weight, body fat mass, and percent body fat were not significantly different between the two groups. - the PSG group showed significantly increased strength of both the dominant and non-dominant knees and shoulders, whereas the CON group did not. - muscular strength did not increase even after resistance exercise in the CON. - the PSG showed significantly increased endurance of the dominant knee and shoulder, whereas the endurance of the CON did not change. Authors conclude that whey protein supplementation promotes muscle mass increase and selective increases in muscular strength and endurance from resistance exercise. Thus, whey protein supplementation is practically effective independently of the normal diet.
Abstract
(1) The purpose of this study was to investigate the effect of whey protein supplementation under dietary control on improvements in muscle mass and function following resistance exercise training. (2) Thirty-two men were randomly assigned to a whey protein supplementation group taking whey protein isolate (PSG, n = 17) and a placebo group (CON, n = 15). Participants were provided with three meals per day corresponding to the estimated individual daily energy intake. The supervised resistance exercise program was conducted 60 min per day, six days per week, for four weeks. (3) Post-intervention, there was a significant interaction between groups in terms of muscle mass increase (p = 0.033, η2 = 0.14), with a greater increase in the PSG. There were also significant interactions between the groups and increases in peak torque of the dominant knee flexors (p = 0.048, η2 = 0.12), dominant shoulder extensors, and non-dominant shoulder extensors (p = 0.028, η2 = 0.15; p = 0.015, η2 = 0.18), and the total work of the dominant knee and shoulder extensors (p = 0.012, η2 = 0.19; p = 0.013, η2 = 0.19), with greater increases in the PSG. (4) These results suggest that whey protein supplementation enhances resistance exercise-induced increase in muscle mass and overall muscular strength and endurance, independent of dietary influence.
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How do previously inactive individuals restructure their time to 'fit in' morning or evening exercise: a randomized controlled trial.
Brooker, PG, Gomersall, SR, King, NA, McMahon, NF, Leveritt, MD
Journal of behavioral medicine. 2023;46(3):429-439
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The number of hours in a day is fixed and finite, distributed between obligatory time (such as time spent working, sleeping, domestic activities, commuting or eating) and discretionary time (the remaining ‘free’ time). The way individuals restructure the timing of their behaviours can influence the effectiveness of exercise, and have important health consequences, depending on what activities are displaced. The aim of this study was to investigate how previously inactive adults restructure their time when they undertake morning or evening exercise. This study was conducted within a larger randomised controlled trial which used a three-armed, randomised controlled trial design, with a 12-week lifestyle intervention. Participants (n = 100) were randomized into one of two intervention groups, or a waitlist control group at a 2:2:1 ratio. Results showed that time spent engaging in physical activity was significantly increased from baseline at both mid- and post-intervention for both intervention groups. Furthermore, participants in both intervention groups reported more time spent sleeping, and less time watching television/playing videogames. Authors conclude that the time for exercise was largely drawn from a discretionary time (watching TV), and the patterns of change in time use was similar when exercise was performed in the morning compared with the evening.
Abstract
The objective of this study was to investigate changes in sedentary and active behaviors when previously inactive adults start exercising in the morning or evening. One-hundred adults with overweight or obesity (BMI ≥ 25 kg/m2) were recruited for a 12-week intervention and randomized to one of three groups: (i) morning exercise (AMEx; 0600-0900); (ii) evening exercise (PMEx; 1600-1900); or (iii) waitlist control. AMEx and PMEx were prescribed self-paced aerobic exercise to achieve a weekly total of 250 min via a combination of supervised and unsupervised training. Sedentary and active behavior times were measured at baseline, mid- and post-intervention using the multimedia activity recall for children and adults. Time spent engaging in physical activity was significantly increased from baseline at both mid- (+ 14-22 min·day-1) and post-intervention (+ 12-19 min·day-1), for AMEx and PMEx. At 12-weeks, participants in both morning and evening exercise groups reported increased time spent Sleeping (+ 36 and + 20 min·day-1, respecitively), and reduced time spent watching TV/playing videogames (- 32 and - 25 min·day-1, respectively). In response to an exercise stimulus, previously inactive adults make encouraging modifications in how they use their time, and the patterns of change are similar with morning and evening exercise.
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Effect of high intensity interval training on arterial stiffness in obese hypertensive women: a randomized controlled trial.
Taha, MM, Aneis, YM, Hasanin, ME, Felaya, EE, Aldhahi, MI, Abdeen, HAA
European review for medical and pharmacological sciences. 2023;27(9):4069-4079
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Hypertension is considered one of the risk factors for cardiovascular disease. Hypertension is a multifactorial condition in which arterial stiffness is one of its manifestations. Exercise is a nonpharmaceutical intervention, and it is known to induce cardiovascular benefits. The aim of this study was to evaluate if the mechanistic effect of high-intensity interval training (HIIT) would affect arterial stiffness parameters in sedentary obese hypertensive women. This study is a randomised controlled trial which enrolled sixty hypertensive women between the ages of 40 and 50 years. Participants were randomly assigned to one of two groups: 1) 12-week of high-intensity interval training or 2) a control group. Results show that HIIT has a beneficial effect on lowering arterial stiffness in obese hypertensive women. Furthermore, HIIT resulted in significant improvements in several metabolic parameters namely blood pressure, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, and triglycerides. Authors conclude that HIIT for 12 weeks reduces cardiometabolic risk factors and improves arterial stiffness indices in obese hypertensive women. Thus, HIIT should be included in the treatment of obese hypertensive women to reduce their risk of cardiovascular disease.
Abstract
OBJECTIVE High-intensity interval training (HIIT) has been linked to a lower risk of cardiovascular disease and mortality. The study's overarching goal is to evaluate the impact of HIIT on arterial stiffness in obese hypertensive women. PATIENTS AND METHODS Sixty obese hypertensive women aged between 40-50 years were randomized to group A (Intervention group, n = 30) or group B (Control group, n = 30). Intervention group received HIIT (4 minutes of cycling at 85-90% of peak HR interspersed with 3-minute active recovery time at 60 - 70% of peak HR, three times per week). Arteriovenous stiffness indicators, the augmentation index corrected for heart rate 75 (AIx@75HR), and oscillometric pulse wave velocity (o-PWV), as well as cardio-metabolic parameters, were assessed before and after 12 weeks of treatment. RESULTS Finding between-group analysis showed a significant difference in AIx@75HR (95% CI: -8.45 to 0.30) , o-PWV ( 95% CI: -1.14 to 0.15), total cholesterol, (95% CI: -31.25 to -1.12), HDL-cholesterol (95% CI: 8.92 to 0.94), LDL-cholesterol (95% CI: -25.35 to -0.06) , and triglycerides (95% CI: -53.58 to -2.51). CONCLUSIONS High-intensity interval training for 12 weeks has a favorable effect on arterial stiffness in obese hypertensive women and lowers associated cardio-metabolic risk factors.
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Effects of branched chain amino acids, l-citrulline, and alpha-glycerylphosphorylcholine supplementation on exercise performance in trained cyclists: a randomized crossover trial.
Harrington, RN
Journal of the International Society of Sports Nutrition. 2023;20(1):2214112
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Exercise-induced fatigue can limit sports performance and training goals. Branched chain amino acids (BCAA) have been shown to prevent fatigue and improve recovery but can also lead to excess ammonia which in turn may contribute to fatigue. Citrulline has been shown to counteract this ammonia accumulation and may increase nutrient delivery to the muscles through promoting nitric oxide synthesis. Alpha-glycerylphosphoryl choline (A-GPC), which releases choline, is thought to increase peak power and delay fatigue in athletes. This randomised, double-blind, placebo-controlled crossover trial of 30 trained male cyclists evaluated supplementation of the combination of BCAA, citrulline and A-GPC for 7 days on the performance in a 20 km cycling time trial and a high intensity endurance cycling (HIEC) test. Outcome measures for both tests were time to completion, peak and average power output and subjective measures of exertion. In the time trial, cyclists had significantly higher peak performance when taking the supplement compared to placebo, whilst they experienced less muscle soreness and greater mental/focus concentration on the placebo. There were no differences between supplement and placebo for time to completion, average power, overall energy, muscle fatigue or levels of exertion. In the HIEC test, there was a significantly longer time to fatigue with the supplement, whilst there was again less muscle soreness with the placebo. There were no differences for muscle fatigue, overall energy or mental focus/concentration. The authors conclude that this combination of nutrients may help improve performance in sports requiring muscle strength and endurance.
Abstract
BACKGROUND Nutrition plays a key role in training and athletic performance and dietary supplements can make a small, but potentially valuable, contribution to achieving peak athletic performance. This study is the first to investigate the effects of supplementation from the combination of BCAAs, L-citrulline, and A-GPC on exercise performance. METHODS In this randomized, double-blind, crossover study 30 male trained cyclists (age: 43.7 ± 8.5 years) completed a 20 km cycling time trial (TT) test and a high intensity endurance cycling (HIEC) test following a 7-day supplementation period with either a supplement containing 8 g BCAAs, 6 g L-citrulline, and 300 mg A-GPC or a placebo (15 g maltodextrin). For each trial, mean values for time to completion, peak and average power output, OMNI rating of perceived exertion, and visual analogue scale (VAS) responses on perceived exertion were computed for the 20 km TT test. Mean values for time to fatigue and VAS responses on perceived exertion were computed for the HIEC test. Procedures for dietary intake and exercise patterns were implemented to achieve consistency throughout the study period. RESULTS There was a significant increase (p = .003) in peak power in the 20 km TT (354.27 ± 87.88 and 321.67 ± 63.65, for supplement and placebo trials, respectively) and a significant increase (p = .001) in time to fatigue in the HIEC test (0:19:49 ± 0:11:13 min and 0:14:33 ± 0:09:59 min, for supplement and placebo trials, respectively) with the test supplement compared to the placebo. With the test supplement, there was an average increase in TT peak power of 11% and an average increase in time to fatigue of 36.2% in the HIEC test compared to the placebo. There was no significant improvement in time to completion, average power, OMNI rating of perceived exertion, or VAS responses on perceived exertion in the TT test and no significant improvement in VAS measures of perceived exertion in the HIEC test. CONCLUSIONS The combination of BCAAs, L-citrulline, and A-GPC used in this study improves cycling performance and may be useful for individuals seeking to improve athletic performance, particularly in disciplines requiring lower body muscular strength and endurance.
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A 2-yr Randomized Controlled Trial on Creatine Supplementation during Exercise for Postmenopausal Bone Health.
Chilibeck, PD, Candow, DG, Gordon, JJ, Duff, WRD, Mason, R, Shaw, K, Taylor-Gjevre, R, Nair, B, Zello, GA
Medicine and science in sports and exercise. 2023;55(10):1750-1760
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Osteoporosis is a bone disease that gradually develops when bone mineral density (BMD) or bone mass decreases and the quality of bone is impaired. This randomised controlled trial conducted over 2 years wanted to test the effects of creatine monohydrate supplementation on BMD at several bone sites during a supervised resistance training and walking program in post menopausal women. 120 were randomly allocated to creatine and 117 to placebo. All participants received a daily supplement of 500 mg of calcium and 10 μg -400 IU of vitamin D. The researchers were particularly interested in finding out whether the creatine group showed improved (BMD) at the femoral neck, lower spine and upper thigh bone also known as the proximal femur which connects the hip joint. Bone density scans, dual-energy X-ray’s and ultrasounds were used to measure BMD and assess areas of bone. Falls and fractures were recorded for a total of 3 years. Dietary intake and physical activity outside of study requirements was assessed using food frequency and exercise questionnaires. Fasting blood and urine analyses along with 24-h urine analysis were taken. The authors conclude that creatine supplementation during a resistance training and walking program had no effect on BMD at the femoral neck, total hip, or lower spine. They further acknowledge relatively low compliance with the creatine supplements, and exercise protocols, along with a high drop out rate. Further studies of larger sample sizes are needed.
Abstract
PURPOSE Our purpose was to examine the effects of 2 yr of creatine monohydrate supplementation and exercise on bone health in postmenopausal women. METHODS Two hundred and thirty-seven postmenopausal women (mean age, 59 yr) were randomized to receive creatine (0.14 g·kg -1 ·d -1 ) or placebo during a resistance training (3 d·wk -1 ) and walking (6 d·wk -1 ) program for 2 yr. Our primary outcome was the femoral neck bone mineral density (BMD), with lumbar spine BMD and proximal femur geometric properties as the secondary outcomes. RESULTS Compared with placebo, creatine supplementation had no effect on BMD of the femoral neck (creatine: 0.725 ± 0.110 to 0.712 ± 0.100 g·cm -2 ; placebo: 0.721 ± 0.102 to 0.706 ± 0.097 g·cm -2 ), total hip (creatine: 0.879 ± 0.118 to 0.872 ± 0.114 g·cm -2 ; placebo: 0.881 ± 0.111 to 0.873 ± 0.109 g·cm -2 ), or lumbar spine (creatine: 0.932 ± 0.133 to 0.925 ± 0.131 g·cm -2 ; placebo: 0.923 ± 0.145 to 0.915 ± 0.143 g·cm -2 ). Creatine significantly maintained section modulus (1.35 ± 0.29 to 1.34 ± 0.26 vs 1.34 ± 0.25 to 1.28 ± 0.23 cm 3 (placebo), P = 0.0011), predictive of bone bending strength, and buckling ratio (10.8 ± 2.6 to 11.1 ± 2.2 vs 11.0 ± 2.6 to 11.6 ± 2.7 (placebo), P = 0.011), predictive of reduced cortical bending under compressive loads, at the narrow part of the femoral neck. Creatine reduced walking time over 80 m (48.6 ± 5.6 to 47.1 ± 5.4 vs 48.3 ± 4.5 to 48.2 ± 4.9 s (placebo), P = 0.0008) but had no effect on muscular strength (i.e., one-repetition maximum) during bench press (32.1 ± 12.7 to 42.6 ± 14.1 vs 30.6 ± 10.9 to 41.4 ± 14 kg (placebo)) and hack squat (57.6 ± 21.6 to 84.4 ± 28.1 vs 56.6 ± 24.0 to 82.7 ± 25.0 kg (placebo)). In the subanalysis of valid completers, creatine increased lean tissue mass compared with placebo (40.8 ± 5.7 to 43.1 ± 5.9 vs 40.4 ± 5.3 to 42.0 ± 5.2 kg (placebo), P = 0.046). CONCLUSIONS Two years of creatine supplementation and exercise in postmenopausal women had no effect on BMD; yet, it improved some bone geometric properties at the proximal femur.