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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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Inflammation moderates the effects of lifestyle modification on neurocognition among individuals with resistant hypertension.
Avorgbedor, F, Blumenthal, JA, Hinderliter, A, Ingle, K, Lin, PH, Craighead, L, Tyson, C, Kraus, W, Sherwood, A, Smith, PJ
Journal of clinical hypertension (Greenwich, Conn.). 2023;25(1):106-110
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Hypertension is one of the primary causes of cardiovascular disease, stroke, Alzheimer’s Disease, and Alzheimer’s Disease and related dementias (AD/ADRD). Among individuals with hypertension, those with resistant hypertension (RH) appear to have the greatest risk of cerebrovascular disease and associated cognitive impairment. The aim of this study was to investigate the potential influence of individual differences in pre-treatment inflammatory profiles on changes in cognition following lifestyle modification among RH participants in the TRIUMPH clinical trial. This study is a report based on the TRIUMPH study which was a randomised clinical trial. One hundred forty patients with RH were randomised with 2:1 allocation to either a 4-month Centre-based Lifestyle intervention or Standardized Education and Physician Advice. Results show that basal levels of elevated peripheral inflammation may represent an intermediate phenotype of risk for cognitive decline. In fact, individuals with higher levels of c-reactive protein at baseline demonstrated greater improvements in Executive Function/Learning following participation in an intensive lifestyle intervention. Authors conclude that their findings may help inform targeted treatments to reduce ADRD among middle-aged and older adults with cardiovascular disease risk factors.
Abstract
Individuals with resistant hypertension (RH) have the greatest risk of cerebrovascular disease and cognitive impairment among individuals with hypertension. Elevated levels of pro-inflammatory cytokines may represent a critical yet unexamined factor influencing the impact of healthy lifestyle changes on cognitive function. We explored the influence of inflammation on changes in cognition following lifestyle modification among individuals with RH participating in the TRIUMPH clinical trial. One hundred forty participants with RH completed a battery of neurocognitive tests along with the inflammatory marker C-reactive protein (hsCRP) and were subsequently randomized to an intensive 4-month lifestyle modification intervention or to education and physician advice control. Results indicated that the effects of lifestyle modification on Executive Function and Learning were moderated by pre-intervention hsCRP levels (P = .049), with treatment efficacy increasing across levels of baseline inflammation levels (low: d = 0.12; mild: d = 0.43; moderate: d = 0.81). We conclude that inflammatory profiles may help identify individuals more likely to improve executive functioning resulting from lifestyle modification.
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Mediterranean Diet and Physical Activity Nudges versus Usual Care in Women with Rheumatoid Arthritis: Results from the MADEIRA Randomized Controlled Trial.
Papandreou, P, Gioxari, A, Daskalou, E, Grammatikopoulou, MG, Skouroliakou, M, Bogdanos, DP
Nutrients. 2023;15(3)
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Rheumatoid arthritis (RA) is one of the most common autoimmune diseases. Various dietary patterns, including the Mediterranean diet (MD), and individual nutrients including certain types of fatty acids and vitamin D, have been investigated for their potential associations with the development and prognosis of RA. The aim of this study was to evaluate the effect of a personalized MD plan delivered through a clinical decisions support system (CDSS) platform versus usual care, in women with an RA diagnosis. This study is a single-blind (statistician), two-arm randomised controlled trial. Patients (n = 40 women with RA) were randomly allocated to the intervention or the control arm. Results show that a 12-week personalized MD plan, paired with physical activity (PA) promotion and delivered with the support of CDSS was successful in improving adherence to the MD, disease activity, PA levels, and a plethora of cardiometabolic outcomes among female patients with RA. Furthermore, disease activity was also associated with body mass index. The overall combined prevalence of overweight and obesity in the sample was high, namely 35% and 10%, respectively. Authors conclude that greater adherence to the MD was associated with an ameliorated dietary fat intake, body weight, body composition, and lower disease activity state. Thus, authors suggest that the adoption of the MD by patients with RA appears to be a feasible anti-inflammatory regime.
Abstract
In rheumatoid arthritis (RA), diet quality and nutritional status have been shown to impact the disease activity and adherence to the Mediterranean diet (MD) has been suggested as an anti-inflammatory regime to improve disease status and reduce cardiovascular risk. The Mediterranean DiEt In Rheumatoid Arthritis (MADEIRA) was a single-blind (statistician), two-arm randomized clinical trial, investigating the effects of a 12-week lifestyle intervention, including a personalized isocaloric MD plan with the promotion of physical activity (PA), supported through a clinical decision support systems (CDSS) platform, versus usual care in women with RA. Forty adult women with RA on remission were randomly allocated (1:1 ratio) to either the intervention or the control arm. The intervention group received personalized MD plans and lifestyle consultation on improving PA levels, whereas the controls were given generic dietary and PA advice, based on the National Dietary Guidelines. The primary outcome was that the difference in the MD adherence and secondary outcomes included change in disease activity (DAS28), anthropometric indices (BodPod), dietary intake, PA, vitamin D concentrations, and blood lipid profiles after 12 weeks from the initiation of the trial. At 3 months post-baseline, participants in the MD arm exhibited greater adherence to the MD compared with the controls (p < 0.001), lower DAS28 (p < 0.001), favorable improvements in dietary intake (p = 0.001), PA (p = 0.002), body weight and body composition (p < 0.001), blood glucose (p = 0.005), and serum 1,25(OH)2D concentrations (p < 0.001). The delivery of the MD and PA promotion through CDSS nudges in women with RA in an intensive manner improves the MD adherence and is associated with beneficial results regarding disease activity and cardiometabolic-related outcomes, compared with the usual care.
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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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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.
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Alternate-Day Fasting Combined with Exercise: Effect on Sleep in Adults with Obesity and NAFLD.
Ezpeleta, M, Gabel, K, Cienfuegos, S, Kalam, F, Lin, S, Pavlou, V, Varady, KA
Nutrients. 2023;15(6)
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Non-alcoholic fatty liver disease (NAFLD) is defined as the presence of 5% or more fat in the liver, confirmed by hepatic imaging or biopsy. Poor sleep may adversely affect insulin sensitivity and inflammatory status, thereby contributing to the development and progression of NAFLD. The aim of this study was to investigate how intermittent fasting combined with exercise impacts body weight and sleep measures in adults with NAFLD. This study was a secondary analysis of a 3-month randomised, controlled, parallel-arm study. Participants were randomized to 1 of 4 intervention groups: alternate-day fasting (ADF) plus exercise, ADF alone, exercise alone, or a no-intervention control group. Results showed that intermittent fasting combined with exercise produced significant reductions in body weight and intrahepatic triglyceride content but no changes in sleep quality, duration, insomnia severity, or risk of obstructive sleep apnoea. Authors conclude that the weight loss induced by ADF combined with exercise does not improve sleep quality, duration, insomnia severity or risk of obstructive sleep apnea in individuals with obesity and NAFLD.
Abstract
Objective: This study investigated how alternate-day fasting (ADF) combined with aerobic exercise impacts body weight and sleep in adults with non-alcoholic fatty liver disease (NAFLD). Methods: Adults with obesity and NAFLD (n = 80) were randomized into one of four groups for 3 months: combination of ADF (600 kcal "fast day," alternated with an ad libitum intake "feast day") and moderate-intensity aerobic exercise (five sessions per week, 60 min/session); ADF alone; exercise alone; or a no-intervention control group. Results: By month 3, body weight and intrahepatic triglyceride content decreased (p < 0.001, group × time interaction) in the combination group versus the exercise group and control group, but not versus the ADF group. Sleep quality, measured by the Pittsburgh Sleep Quality Inventory (PSQI), did not change in the combination group (baseline: 6.0 ± 0.7; month 3: 5.6 ± 0.7), ADF group (baseline: 8.9 ± 1.0; month 3: 7.5 ± 0.8), or exercise group (baseline: 6.4 ± 0.6; month 3: 6.7 ± 0.6), versus controls (baseline: 5.5 ± 0.7; month 3: 4.6 ± 0.5). Wake time, bedtime, sleep duration, and insomnia severity did not change (no group x time interaction) over the course of the study in any group. Risk for obstructive sleep apnea was present in 30% of combination subjects, 75% of ADF subjects, 40% of exercise subjects, and 75% of controls, and did not change in the intervention groups, versus controls, by month 3. No associations were observed between changes in body weight, intrahepatic triglyceride content, and any sleep outcome. Conclusions: The weight loss induced by ADF combined with exercise does not improve sleep quality, duration, insomnia severity, or risk of obstructive sleep apnea in individuals with NAFLD.
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Pre-sleep Protein Ingestion Increases Mitochondrial Protein Synthesis Rates During Overnight Recovery from Endurance Exercise: A Randomized Controlled Trial.
Trommelen, J, van Lieshout, GAA, Pabla, P, Nyakayiru, J, Hendriks, FK, Senden, JM, Goessens, JPB, van Kranenburg, JMX, Gijsen, AP, Verdijk, LB, et al
Sports medicine (Auckland, N.Z.). 2023;53(7):1445-1455
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Protein intake prior to overnight sleep has been shown to stimulate muscle protein synthesis overnight and increase muscle mass. This randomised, placebo-controlled, double-blind study of 36 healthy young men compared the effects of pre-sleep casein and whey protein, following a bout of endurance training in the evening. Outcome measures were overnight protein synthesis rates in microfibrils (the contractile organelle of muscle cells) and mitochondria (the energy producing organelle). Ingestion of whey protein resulted in a statistically significantly higher rates of both microfibrillar and mitochondrial protein synthesis compared to placebo. Results for casein were intermediate and not significantly different from either placebo or whey. Both casein and whey protein intake led to a significant increase in circulating total and essential amino acids overnight, compared to placebo, with the whey protein leading to a quicker and casein to a slower but more sustained increase, although the overall increase (area under the curve) did not differ between the two protein groups. There were no differences in sleep, hunger or energy intake at breakfast between groups. The authors conclude that pre-sleep protein intake following endurance exercise increases both microfibrillar and mitochondrial protein synthesis overnight, with casein not being superior to whey.
Abstract
BACKGROUND Casein protein ingestion prior to sleep has been shown to increase myofibrillar protein synthesis rates during overnight sleep. It remains to be assessed whether pre-sleep protein ingestion can also increase mitochondrial protein synthesis rates. Though it has been suggested that casein protein may be preferred as a pre-sleep protein source, no study has compared the impact of pre-sleep whey versus casein ingestion on overnight muscle protein synthesis rates. OBJECTIVE We aimed to assess the impact of casein and whey protein ingestion prior to sleep on mitochondrial and myofibrillar protein synthesis rates during overnight recovery from a bout of endurance-type exercise. METHODS Thirty-six healthy young men performed a single bout of endurance-type exercise in the evening (19:45 h). Thirty minutes prior to sleep (23:30 h), participants ingested 45 g of casein protein, 45 g of whey protein, or a non-caloric placebo. Continuous intravenous L-[ring-13C6]-phenylalanine infusions were applied, with blood and muscle tissue samples being collected to assess overnight mitochondrial and myofibrillar protein synthesis rates. RESULTS Pooled protein ingestion resulted in greater mitochondrial (0.087 ± 0.020 vs 0.067 ± 0.016%·h-1, p = 0.005) and myofibrillar (0.060 ± 0.014 vs 0.047 ± 0.011%·h-1, p = 0.012) protein synthesis rates when compared with placebo. Casein and whey protein ingestion did not differ in their capacity to stimulate mitochondrial (0.082 ± 0.019 vs 0.092 ± 0.020%·h-1, p = 0.690) and myofibrillar (0.056 ± 0.009 vs 0.064 ± 0.018%·h-1, p = 0.440) protein synthesis rates. CONCLUSIONS Protein ingestion prior to sleep increases both mitochondrial and myofibrillar protein synthesis rates during overnight recovery from exercise. The overnight muscle protein synthetic response to whey and casein protein does not differ. CLINICAL TRIAL REGISTRATION NTR7251 .
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Betaine supplementation improves CrossFit performance and increases testosterone levels, but has no influence on Wingate power: randomized crossover trial.
Zawieja, E, Durkalec-Michalski, K, Sadowski, M, Główka, N, Chmurzynska, A
Journal of the International Society of Sports Nutrition. 2023;20(1):2231411
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Betaine nutritional supplementation is often used by individuals who want to increase their athletic performance as it has been hypothesised to increase muscle strength and power. However, studies on this have been inconsistent. One study has shown no benefit of supplementation on muscle strength, however two have shown a benefit of betaine on muscle endurance, which is essential to perform cross fit-based exercises. The aim of this study was to determine the effect of betaine on body composition, cross fit performance, muscle power, and certain hormones after 3 weeks of supplementation. The results showed that workout performance was improved with betaine supplementation, however this did not translate into changes in body composition. Testosterone levels were increased by betaine supplementation. Individuals who had genetic variations that meant that their betaine requirements may be higher showed no benefit of taking betaine for cross-fit performance or any of the outcomes measured. There was also no difference to any of the outcomes with differing betaine doses (2.5 and 5.0 g/d). It was concluded that betaine supplementation may improve cross-fit performance and testosterone levels. However individuals with genetic variations that may mean their requirements for betaine are higher showed no benefit of supplementation on cross-fit performance.
Abstract
BACKGROUND Because betaine (BET) supplementation may improve muscular strength and endurance, it seems plausible that BET will also influence CrossFit performance (CF). PURPOSE The aim of this study was to evaluate the effects of three weeks of BET supplementation on body composition, CF performance, muscle power in the Wingate anaerobic test (WAnT), and the concentrations of selected hormones. The secondary aims were to analyze the effectiveness of two different BET doses (2.5 and 5.0 g/d) and their interaction with the methylenetetrahydrofolate reductase (MTHFR) genotype. METHODS The study was designed in a double-blinded randomized cross-over fashion. Forty-three CF practitioners completed the entire study. CF performance was measured using the Fight Gone Bad (FGB) workout and muscle power was evaluated in a 30-second WAnT. Body composition was determined by air-displacement plethysmography. Blood was drawn to assess hormone concentrations. The C677T single nucleotide polymorphism (rs180113) in the MTHFR gene was analyzed. RESULTS FGB total improved with BET by 8.7 ± 13.6% (p < 0.001), but no significant changes were observed with placebo (- 0.4 ± 10.0%, p = 0.128). No changes were also observed in WAnT and body composition. After BET supplementation testosterone concentration increased by 7.0 ± 15.4% with BET (p = 0.046) (no change with placebo: 1.5 ± 19.6%, p = 0.884) but had no effect on concentrations of insulin-like growth factor or cortisol. Finally, there were no significant interactions between MTHFR genotype and BET dose in any outcome. CONCLUSIONS BET supplementation may improve CF performance and increase testosterone concentration. However, there was no evidence of a difference between dosages (2.5 and 5.0 g/d) and MTHFR genotypes. The trial was registered on clinicaltrials.gov (NCT03702205) on 10 October 2018.
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An Energy-Reduced Mediterranean Diet, Physical Activity, and Body Composition: An Interim Subgroup Analysis of the PREDIMED-Plus Randomized Clinical Trial.
Konieczna, J, Ruiz-Canela, M, Galmes-Panades, AM, Abete, I, Babio, N, Fiol, M, Martín-Sánchez, V, Estruch, R, Vidal, J, Buil-Cosiales, P, et al
JAMA network open. 2023;6(10):e2337994
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The Mediterranean diet (MedDiet), which focuses on whole grains, lean meat, fruits, vegetables, and low amounts of minimally processed foods has been shown in previous research to improve body composition and decrease fat storage around the middle. This randomised control trial of 1556 older adults aimed to determine the effects of combining a 30% lower energy version of the MedDiet in combination with physical exercise on body composition. After 3 years, the results showed that compared to a normal MedDiet without exercise, the lower energy version in combination with exercise improved body composition by decreasing total fat, and the fat stored around the organs and increasing muscle mass. However, benefits were more pronounced after 1 year and decreased slightly at 3 years. It was concluded that a low energy MedDiet in combination with physical activity may be able to improve the body composition of overweight and older adults with obesity. This study could be used by healthcare professionals to recommend a low energy MedDiet to older adults to promote weight loss, whilst attenuating muscle loss associated with ageing.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The addition of exercise to an energy-reduced diet, which focuses on whole grains, healthy fats, lean protein, and fruits and vegetables can emphasise positive effects on body composition in older adults.
- However, there is a loss of lean mass associated with this type of diet (contrary to author conclusions) and measures should be taken to monitor and increase protein intake to prevent or limit this loss.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
This study aimed to determine the long-term effects of an energy reduced MedDiet in combination with physical activity on body composition.
Methods
- This is a predetermined 3-year interim analysis of a 6-year single-blind, randomised control trial of 1556 individuals aged 55-75 who are overweight or obese with metabolic syndrome.
- 760 individuals on 30% energy reduced MedDiet with limited processed foods, plus 45 minutes walking 6 days per week and behavioural and motivational support. [Intervention group]
- 761 on standard MedDiet without physical activity. [Control]
Results
Within group comparisons showed that individuals in the intervention group lost (P value represents baseline vs year 3):
- Total fat mass percentage (1-year vs baseline, −1.14%; 95% CI, −1.32% to −0.96%; 3-year vs baseline, −0.52%; 95% CI, −0.71% to −0.33% P=<0.001)
- Absolute visceral fat (1-year vs baseline, −154 g; 95% CI, −191 to −116 g; 3-year vs baseline, −75.1 g, 95% CI, −115 to −35.3 g P=<0.001)
- Absolute total fat after 1 year (mean change at 1 year vs baseline, −1677 g; 95% CI, −1930 to −1424 g) but regained some at year 3 (mean change at 3 years vs baseline, −1018 g; 95% CI, −1280 to −756 g P=<0.001)
- Absolute lean mass (mean change at 1 year vs baseline −300 g; 95% CI, −439 to −162 g) with further losses at year 3 (−626 g; 95% CI, −770 to −483 g P=0.001).
Within group comparisons also showed significantly increased:
- Total lean mass percentage, which was greater at year 1 than year 3 (1-year vs baseline, 1.07%; 95%CI, 0.90%-1.25%; 3-year vs baseline, 0.47%; 95% CI, 0.29%-0.65% P=<0.001).
As a result of total fat loss and some lean mass in the intervention group, the lean:fat mass ratio improved and was unchanged in the control group (between group differences (P=<0.001).
Compared to women, men may find the MedDiet + exercise more beneficial as it was shown that body composition changes were slightly more pronounced in men.
Conclusion
An energy-reduced MedDiet plus exercise emphasised positive changes to body composition compared to standard MedDiet in older adults who are overweight or have obesity.
Clinical practice applications:
- The recommendation of a reduced energy MedDiet in combination with physical activity to older people who are overweight or obese may improve body composition.
- Although lean mass loss slowed between years 1 and 3, other practices should be employed to attenuate the loss of lean mass associated with an energy-reduced MedDiet and ageing.
Considerations for future research:
- The research has not yet concluded but when it does, it will address the incidence of cardiovascular disease along with body composition changes.
- It will also look at long-term effects of the diet to determine longevity.
- Future research could focus on how to limit lean mass loss through the possibility of changing the type of exercise that accompanies the MedDiet.
Abstract
IMPORTANCE Strategies targeting body composition may help prevent chronic diseases in persons with excess weight, but randomized clinical trials evaluating lifestyle interventions have rarely reported effects on directly quantified body composition. OBJECTIVE To evaluate the effects of a lifestyle weight-loss intervention on changes in overall and regional body composition. DESIGN, SETTING, AND PARTICIPANTS The ongoing Prevención con Dieta Mediterránea-Plus (PREDIMED-Plus) randomized clinical trial is designed to test the effect of the intervention on cardiovascular disease prevention after 8 years of follow-up. The trial is being conducted in 23 Spanish research centers and includes men and women (age 55-75 years) with body mass index between 27 and 40 and metabolic syndrome. The trial reported herein is an interim subgroup analysis of the intermediate outcome body composition after 3-year follow-up, and data analysis was conducted from February 1 to November 30, 2022. Of 6874 total PREDIMED-Plus participants, a subsample of 1521 individuals, coming from centers with access to a dual energy x-ray absorptiometry device, underwent body composition measurements at 3 time points. INTERVENTION Participants were randomly allocated to a multifactorial intervention based on an energy-reduced Mediterranean diet (MedDiet) and increased physical activity (PA) or to a control group based on usual care, with advice to follow an ad libitum MedDiet, but no physical activity promotion. MAIN OUTCOMES AND MEASURES The outcomes (continuous) were 3-year changes in total fat and lean mass (expressed as percentages of body mass) and visceral fat (in grams), tested using multivariable linear mixed-effects models. Clinical relevance of changes in body components (dichotomous) was assessed based on 5% or more improvements in baseline values, using logistic regression. Main analyses were performed in the evaluable population (completers only) and in sensitivity analyses, multiple imputation was performed to include data of participants lost to follow-up (intention-to-treat analyses). RESULTS A total of 1521 individuals were included (mean [SD] age, 65.3 [5.0] years; 52.1% men). In comparison with the control group (n=761), participants in the intervention arm (n=760) showed greater reductions in the percentage of total fat (between group differences after 1-year, -0.94% [95% CI, -1.19 to -0.69]; 3 years, -0.38% [95% CI, -0.64 to -0.12] and visceral fat storage after 1 year, -126 g [95% CI, -179 to -73.3 g]; 3 years, -70.4 g [95% CI, -126 to -15.2 g] and greater increases in the percentage of total lean mass at 1 year, 0.88% [95% CI, 0.63%-1.12%]; 3-years 0.34% [95% CI, 0.09%-0.60%]). The intervention group was more likely to show improvements of 5% or more in baseline body components (absolute risk reduction after 1 year, 13% for total fat mass, 11% for total lean mass, and 14% for visceral fat mass; after 3-years: 6% for total fat mass, 6% for total lean mass, and 8% for visceral fat mass). The number of participants needed to treat was between 12 and 17 to attain at least 1 individual with possibly clinically meaningful improvements in body composition. CONCLUSIONS AND RELEVANCE The findings of this trial suggest a weight-loss lifestyle intervention based on an energy-reduced MedDiet and physical activity significantly reduced total and visceral fat and attenuated age-related losses of lean mass in older adults with overweight or obesity and metabolic syndrome. Continued follow-up is warranted to confirm the long-term consequences of these changes on cardiovascular clinical end points. TRIAL REGISTRATION isrctn.org Identifier: ISRCTN89898870.