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1.
Rev Med Suisse ; 20(871): 854-857, 2024 Apr 24.
Artículo en Francés | MEDLINE | ID: mdl-38665107

RESUMEN

An increasing number of people are surviving cancer in Switzerland : 163,450 people were still alive in 2006 after a cancer diagnosis less than ten years prior, compared to 210,350 in 2016. However, most have to cope with debilitating emotional and physical aftereffects. A new 12-week rehabilitation program aims to restore patients' abilities. It consists of group-led therapies: adapted physical activity, psycho-oncology, dietetics, management of cognitive disorders, and integrative medicine. The first 116 patients who benefited from the program reported a general reduction in symptoms at the end of the program, an improvement that lasts even after 9 months, although fatigue and mood become concerning again. Some express a desire for post-rehabilitation follow-up.


De plus en plus de personnes survivent au cancer en Suisse : 163 450 personnes étaient encore en vie après un diagnostic de cancer remontant à moins de dix ans en 2006, contre 210 350 en 2016. La plupart doivent toutefois faire face à des séquelles émotionnelles et physiques invalidantes. Un nouveau programme de réadaptation de 12 semaines vise à restaurer les capacités des patients. Il est composé de thérapies menées en groupe : activité physique adaptée, psycho-oncologie, diététique, gestion des troubles cognitifs et médecine intégrative. Les 116 premiers patients bénéficiaires expriment une diminution générale des symptômes à l'issue du programme, une amélioration qui perdure après 9 mois, même si la fatigue et le moral redeviennent préoccupants. Certains expriment le souhait d'un suivi post-réadaptation.


Asunto(s)
Neoplasias , Humanos , Neoplasias/rehabilitación , Neoplasias/psicología , Suiza/epidemiología , Supervivientes de Cáncer/psicología , Emociones , Fatiga/psicología , Fatiga/rehabilitación , Ejercicio Físico/psicología , Ejercicio Físico/fisiología
2.
J Int Soc Sports Nutr ; 21(1): 2341903, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38626029

RESUMEN

Protein supplementation often refers to increasing the intake of this particular macronutrient through dietary supplements in the form of powders, ready-to-drink shakes, and bars. The primary purpose of protein supplementation is to augment dietary protein intake, aiding individuals in meeting their protein requirements, especially when it may be challenging to do so through regular food (i.e. chicken, beef, fish, pork, etc.) sources alone. A large body of evidence shows that protein has an important role in exercising and sedentary individuals. A PubMed search of "protein and exercise performance" reveals thousands of publications. Despite the considerable volume of evidence, it is somewhat surprising that several persistent questions and misconceptions about protein exist. The following are addressed: 1) Is protein harmful to your kidneys? 2) Does consuming "excess" protein increase fat mass? 3) Can dietary protein have a harmful effect on bone health? 4) Can vegans and vegetarians consume enough protein to support training adaptations? 5) Is cheese or peanut butter a good protein source? 6) Does consuming meat (i.e., animal protein) cause unfavorable health outcomes? 7) Do you need protein if you are not physically active? 8) Do you need to consume protein ≤ 1 hour following resistance training sessions to create an anabolic environment in skeletal muscle? 9) Do endurance athletes need additional protein? 10) Does one need protein supplements to meet the daily requirements of exercise-trained individuals? 11) Is there a limit to how much protein one can consume in a single meal? To address these questions, we have conducted a thorough scientific assessment of the literature concerning protein supplementation.


Asunto(s)
Proteínas en la Dieta , Resistencia Física , Humanos , Resistencia Física/fisiología , Ejercicio Físico/fisiología , Suplementos Dietéticos , Músculo Esquelético/fisiología
3.
J Sports Sci Med ; 23(1): 126-135, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38455428

RESUMEN

Percussive massage (PM) is an emerging recovery treatment despite the lack of research on its effects post-eccentric exercise (post-EE). This study investigated the effects of PM treatments (immediately, 24, 48, and 72 h post-EE) on the maximal isometric torque (MIT), range of motion (ROM), and an 11-point numerical rating scale (NRS) of soreness of the nondominant arm's biceps brachii from 24-72 h post-EE. Seventeen untrained, college-aged subjects performed 60 eccentric elbow flexion actions with their nondominant arms. Nine received 1 minute of PM, versus eight who rested quietly (control [CON]). In order, NRS, ROM, and MIT (relative to body mass) were collected pre-eccentric exercise (pre-EE) and after treatment (AT) at 24, 48, and 72 h post-EE. NRS was also collected before treatment (BT). Electromyographic (EMG) and mechanomyographic (MMG) amplitudes were collected during the MIT and normalized to pre-EE. There were no interactions for MIT, EMG, or MMG, but there were interactions for ROM and NRS. For ROM, the PM group had higher values than the CON 24-72 h by ~6-8°, a faster return to pre-EE (PM: 48 h, CON: 72 h), and exceeded their pre-EE at 72 h by ~4°. The groups' NRS values did not differ BT 24-72 h; however, the PM group lowered their NRS from BT to AT within every visit by ~1 point per visit, which resulted in them having lower values than the CON from 24-72 h by ~2-3 points. Additionally, the PM group returned their NRS to pre-EE faster than the CON (PM: BT 72 h, CON: never). In conclusion, PM treatments may improve ROM without affecting isometric strength or muscle activation 24-72 h post-EE. Although the PM treatments did not enhance the recovery from delayed onset muscle soreness until 72 h, they consistently provided immediate, temporary relief when used 24-72 h post-EE.


Asunto(s)
Ejercicio Físico , Mialgia , Humanos , Adulto Joven , Ejercicio Físico/fisiología , Mialgia/etiología , Mialgia/terapia , Músculo Esquelético/fisiología , Brazo , Masaje
4.
Nutrients ; 16(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38474848

RESUMEN

In recent years, postbiotics have increased in popularity, but the potential relevancy of postbiotics for augmenting exercise performance, recovery, and health is underexplored. A systematic literature search of Google Scholar and PubMed databases was performed with the main objective being to identify and summarize the current body of scientific literature on postbiotic supplementation and outcomes related to exercise performance and recovery. Inclusion criteria for this systematic review consisted of peer-reviewed, randomized, double-blind, and placebo-controlled trials, with a population including healthy men or women >18 years of age. Studies required the incorporation of a postbiotic supplementation regimen and an outcome linked to exercise. Search terms included paraprobiotics, Tyndallized probiotics, ghost biotics, heat-killed probiotics, inactivated probiotics, nonviable probiotics, exercise, exercise performance, and recovery. Only investigations written in English were considered. Nine peer-reviewed manuscripts and two published abstracts from conference proceedings were included and reviewed. Supplementation periods ranged from 13 days to 12 weeks. A total of 477 subjects participated in the studies (n = 16-105/study) with reported results spanning a variety of exercise outcomes including exercise performance, recovery of lost strength, body composition, perceptual fatigue and soreness, daily logs of physical conditions, changes in mood states, and biomarkers associated with muscle damage, inflammation, immune modulation, and oxidative stress. Early evidence has provided some indication that postbiotic supplementation may help to support mood, reduce fatigue, and increase the readiness of athletes across several weeks of exercise training. However, more research is needed to further understand how postbiotics may augment health, resiliency, performance, and recovery. Future investigations should include longer supplementation periods spanning a wider variety of competitive athletes and exercising populations.


Asunto(s)
Ejercicio Físico , Probióticos , Masculino , Humanos , Femenino , Ejercicio Físico/fisiología , Estrés Oxidativo , Atletas , Suplementos Dietéticos , Ensayos Clínicos Controlados Aleatorios como Asunto
5.
Curr Opin Clin Nutr Metab Care ; 27(3): 219-225, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38386361

RESUMEN

PURPOSE OF REVIEW: Renal cachexia is a deleterious condition characterized by weight loss, muscle wasting and loss of physical function, quality of life, and increased mortality. Multimodal treatment strategies utilizing exercise and nutrition interventions have been recently suggested although the evidence base is still in its infancy. This paper aimed to review the current literature surrounding the use of exercise and nutrition for renal cachexia. MAIN FINDINGS: Evidence from systematic reviews and narrative reviews indicates that resistance training (RT) is proven to have beneficial effects on improving muscle strength and in some cases physical function, although effects on muscle mass are mixed and inconclusive. Further, combined RT and aerobic training (AT) may have also beneficial effects on overall functional capacity and there appears to be no superior mode of protocol (inter/intra-dialysis vs. home-based). For nutrition, there is new data from systematic review of studies indicating that oral nutritional supplementation (ONS) may have beneficial effects on nutritional status (e.g. body mass index, plasma albumin and handgrip strength). Omega-3 fatty acids have been shown to have anti-inflammatory effects in haemodialysis patients from two recent systematic reviews, and evidence from other populations groups indicate they may be beneficial for improving muscle mass and strength. SUMMARY: Evidence is accumulating for individual exercise and nutrition components but specific multimodal treatment studies in renal cachexia need to be urgently undertaken.


Asunto(s)
Caquexia , Calidad de Vida , Humanos , Caquexia/etiología , Caquexia/terapia , Fuerza de la Mano , Ejercicio Físico/fisiología , Estado Nutricional
6.
Am J Prev Med ; 66(6): 1078-1088, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38309672

RESUMEN

INTRODUCTION: Physical activity (PA) promotion combined with multimicronutrient supplementation (MMNS) among school-age children may reduce fat mass accrual and increase muscle mass through different mechanisms and so benefit child health. This study determined the efficacy of combined interventions on body composition among South African schoolchildren and determined if micronutrients mediate these effects. STUDY DESIGN: Longitudinal cluster randomized controlled trial of children followed from 2019 to 2021. Statistical analyses carried from 2022 to 2023. SETTING/PARTICIPANTS: A total of 1,304 children 6-12 years of age recruited from public schools in Gqeberha, South Africa. INTERVENTION: Children were randomized by classes to either: (a) a physical activity group (PA); (b) a MMNS group; (c) a physical activity + multimicronutrient supplementation group (PA + MMNS); and (d) a placebo control group. MAIN OUTCOME MEASURES: Trajectories of overall and truncal fat free mass (FFM) and fat mass (FM) estimates in modeled at 9 and 21 months using latent growth curve models (LGCM). Changes in micronutrient concentrations at 9 months from baseline. RESULTS: An increased FFM trajectory was found among children in the MMNS arm at 9 months (Beta 0.16, 95% CI = 0.12, 0.31). The PA and MMNS arms both had positive indirect effects on this trajectory at 9 months (Beta 0.66, 95% CI = 0.44, 0.88 and Beta 0.32 95% CI = 0.1 0.5, respectively) and similarly at 21 months when mediated by zinc concentration changes. A reduced FM trajectory was found among children in the PA promotion arm at 9 months when using this collection point as the referent intercept. This arm was inversely associated with the FM trajectory at 9 months when mediated by zinc changes. CONCLUSIONS: PA and MMNS promotion in school-based interventions directly contributed to reductions in FM and increased FFM among South African children and indirectly through changes in micronutrient status. TRIAL REGISTRATION: ISRCTN, ISRCTN29534081. Registered on August 9, 2018 Institutional review board: Ethikkommission Nordwest- und Zentralschweiz" (EKNZ, project number: Req-2018-00608). Date of approval: 2018.


Asunto(s)
Composición Corporal , Suplementos Dietéticos , Ejercicio Físico , Micronutrientes , Humanos , Sudáfrica , Micronutrientes/administración & dosificación , Niño , Masculino , Femenino , Ejercicio Físico/fisiología , Estudios Longitudinales
7.
Int J Sports Physiol Perform ; 19(4): 356-364, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38237580

RESUMEN

PURPOSE: To examine the impact of oral contraceptive (OC) phases on performance, physiological, and subjective responses to prolonged, intensive exercise when carbohydrate (CHO) stores are reduced. METHODS: Ten well-trained female cyclists using monophasic OC completed 4 identical trials (>150 min) under conditions of in-trial 60-g·h-1 CHO supplementation (CHO+) or placebo (CHO-) during the sugar- (SUG) and active-pill (ACT) phases of their OC cycle. Each trial comprised two 400-kcal time trials (TT) separated by 1 hour of submaximal cycling at first ventilatory threshold. RESULTS: Change in completion time from TT1 to TT2 was minimized in CHO+ compared with CHO- (4.06 [2.55] vs 6.08 [5.33] min; P = .019, effect size = -0.36). An interaction effect of OC and CHO was observed for time to complete TT (P = .006), mean TT power (P = .002), mean TT heart rate (P = .002), and posttrial emotional balance (P = .020) and negative emotional state (P = .033). In ACT, mean TT power and heart rate were higher in CHO+ when compared with CHO-, resulting in faster TTs in CHO+ and improved posttrial emotional well-being. When CHO was not supplemented, TT power and heart rate were higher in SUG when compared with ACT, resulting in faster TTs in SUG and improved posttrial emotional balance. CONCLUSION: CHO depletion during ACT negatively influenced TT performance and emotional well-being when compared with SUG. Irrespective of OC pill phase, CHO supplementation should be prioritized to sustain performance and improve postexercise recovery-stress balance.


Asunto(s)
Carbohidratos de la Dieta , Ejercicio Físico , Humanos , Femenino , Ejercicio Físico/fisiología , Glucemia , Ciclismo/fisiología , Suplementos Dietéticos , Anticonceptivos Orales , Resistencia Física/fisiología
8.
J Am Nutr Assoc ; 43(4): 384-396, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38241335

RESUMEN

Objective: This overview of systematic reviews (OoSRs) aimed, firstly, to systematically review, summarize, and appraise the findings of published systematic reviews with or without meta-analyses that investigate the effects of branched-chain amino acids (BCAA) on post-exercise recovery of muscle damage biomarkers, muscle soreness, and muscle performance. The secondary objective was to re-analyze and standardize the results of meta-analyses using the random-effects Hartung-Knapp-Sidik-Jonkman (HKSJ) method.Methods: The methodological quality of the reviews was assessed using A Measurement Tool to Assess Systematic Reviews 2.We searched on five databases (i.e., PubMed, Web of Science, Scopus, SPORTDiscus, ProQuest) for systematic reviews with or without meta-analyses that investigated the effects of BCAA supplementation on the post-exercise recovery of muscle damage biomarkers, muscle soreness, and muscle performance.Results: Eleven systematic reviews (seven with meta-analyses) of individual studies were included. Evidence suggests BCAA ingestion attenuates creatine kinase (CK) levels (medium effects) and muscle soreness (small effects) immediately post-exercise and accelerates their recovery process, with trivial-to-large effects for CK levels and small-to-large effects for muscle soreness. BCAA supplementation has no effect on lactate dehydrogenase, myoglobin, and muscle performance recovery. The re-analyses with HKSJ method using the original data reported a slight change in results significance, concluding the same evidence as the original results. The major flaws found in the analyzed reviews were the absence of justification for excluding studies, and the lack of provision of sources of funding for primary studies and sources of conflict of interest and/or funding description.Conclusions: BCAA supplementation is an effective method to reduce post-exercise muscle damage biomarkers, particularly CK levels, and muscle soreness, with no effect on muscle performance. Future systematic reviews with/without meta-analyses, with greater methodological rigor, are needed.


This is the first overview of systematic reviews investigating the impact of BCAA supplementation on muscle damage biomarkers, muscle soreness, and muscle performance post-exercise recovery.BCAA supplementation reduces creatine kinase levels and muscle soreness, especially when consuming a high dose of BCAA longitudinally.BCAA supplementation has no effect on muscle performance post-exercise recovery.


Asunto(s)
Aminoácidos de Cadena Ramificada , Suplementos Dietéticos , Ejercicio Físico , Músculo Esquelético , Mialgia , Aminoácidos de Cadena Ramificada/administración & dosificación , Humanos , Ejercicio Físico/fisiología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Músculo Esquelético/metabolismo , Biomarcadores/sangre , Creatina Quinasa/sangre , Recuperación Después del Ejercicio
9.
Free Radic Biol Med ; 211: 12-23, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38092272

RESUMEN

BACKGROUND: The increase in blood pressure (BP) levels in the postmenopausal period can be partly explained by the decrease in nitric oxide synthases (NOS). OBJECTIVE: To investigate the acute and one-week effects of beetroot juice nitrate-rich (BRJ-NO3-rich) ingestion on cardiovascular and autonomic performance in response to submaximal aerobic exercise in postmenopausal women with systemic arterial hypertension (SAH) who are physically inactive. METHODS: Fourteen postmenopausal women with SAH [mean (SD) age: 59(4) y; BMI (kg/m2): 29.2(3.1)] completed submaximal aerobic exercise bouts after an acute and a one-week intervention with BRJ in a placebo-controlled, randomized, triple-blind, crossover design. Participants ingested either BRJ (800 mg of NO3-) or placebo acutely and drank either BRJ (400 mg of NO3-) or placebo every day for the next six days. After two and ½ hours, they performed a session of aerobic submaximal aerobic exercise, and their systolic BP (SBP) and diastolic BP (DBP), flow-mediated dilation (FMD), heart rate (HR) recovery, and HR variability were measured. RESULTS: In the post-exercise recovery period, SBP dropped significantly in the BRJ-NO3-rich group (-9.28 mmHg [95%CI: -1.68 to -16.88] ES: -0.65, p = 0.019) compared to placebo after acute ingestion. The FMD values increased after acute BRJ-NO3-rich on post-exercise (3.18 % [0.36 to 5.99] ES: 0.87, p = 0.031). After the one-week intervention, FMD values were higher in the BRJ-NO3-rich group before (4.5 % [1.62 to 7.37] ES: 1.21, p = 0.005) and post-exercise measurements (4.2 % [1.52 to 6.87] ES: 1.22, p = 0.004) vs. placebo. HRV indices with remarkable parasympathetic modulation to heart recovered faster on the BRJ-NO3-rich group than placebo group. No between-group differences were identified in values of HR post-exercise recovery in the 30s, 60s, 120s, 180s, and 300s. CONCLUSIONS: Acute and short-term BRJ-NO3-rich ingestion may enhance cardiovascular and autonomic behavior in response to aerobic exercise in postmenopausal women diagnosed with SAH. CLINICAL TRIAL REGISTRY NUMBER: https://clinicaltrials.gov/ct2/show/NCT05384340.


Asunto(s)
Beta vulgaris , Hipertensión , Humanos , Femenino , Persona de Mediana Edad , Nitratos/farmacología , Posmenopausia , Suplementos Dietéticos , Jugos de Frutas y Vegetales , Hipertensión/terapia , Ejercicio Físico/fisiología , Presión Sanguínea , Ingestión de Alimentos , Método Doble Ciego , Estudios Cruzados
10.
Obesity (Silver Spring) ; 32(2): 234-236, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37849057

RESUMEN

Contemporary antiobesity medications (AOMs) are highly efficacious for the treatment of obesity and obesity-related comorbidities. Given this effectiveness, lifestyle factors within the context of AOM treatments need to refocus and move away from efforts to enhance weight loss. Rather, lifestyle considerations should pivot to being complementary to the benefits realized with AOM treatment and be redirected to enhancing holistic patient health and well-being. Physical activity is an important lifestyle behavior that contributes to many health benefits both in conjunction with, and in the absence of, weight loss. Physical activity improves cardiorespiratory fitness, muscle strength, and physical function. Physical activity may attenuate the loss of lean mass that is observed with AOM treatments and may enhance the quality and function of muscle. Physical activity is a key behavior for holistic health within this era of contemporary AOMs that warrants appropriate attention within the clinical care of patients.


Asunto(s)
Fármacos Antiobesidad , Obesidad , Humanos , Obesidad/tratamiento farmacológico , Ejercicio Físico/fisiología , Fármacos Antiobesidad/uso terapéutico , Fuerza Muscular , Pérdida de Peso/fisiología
11.
J Athl Train ; 59(3): 310-316, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37248364

RESUMEN

CONTEXT: Handheld percussive massage devices (ie, massage guns) are a relatively new and under-researched recovery tool. These tools are intended to increase range of motion and reduce muscle soreness by delivering targeted vibration to soft tissues. Empirical knowledge about the potential influence of these devices on perceptual recovery and the recovery of performance characteristics after exercise is scarce. OBJECTIVE: To investigate the effect of a 5-minute massage gun application, using a commercially available device, on physical and perceptual recovery after a strenuous bout of lower body exercise. DESIGN: Controlled laboratory study. SETTING: Physiology laboratory. PATIENTS OR OTHER PARTICIPANTS: A total of 65 active young adults (age = 21.3 ± 1.4 years; age range = 18-30 years; 34 women: height = 165.8 ± 6.1 cm, mass = 66.0 ± 7.4 kg; 31 men: height = 181.1 ± 6.0 cm, mass = 81.5 ± 11.8 kg). INTERVENTION(S): Participants applied a massage gun on the calf muscles of 1 leg after strenuous exercise (massage gun recovery group) for 5 minutes and used no recovery intervention on the other leg (control group). MAIN OUTCOME MEASURE(S): Ankle range of motion, calf circumference, isometric strength, calf endurance, and perceived muscle soreness measures were collected at baseline and at various points after lower body exercise. RESULTS: No significant group × time interactions were recorded for any of the performance or perceptual measures (P values > .05). Effect sizes were mostly unclear, except for a small increase in perceived muscle soreness in the massage gun recovery group compared with the control group immediately (d = -0.35) and 4 hours (d = -0.48) postrecovery. CONCLUSIONS: Massage guns appeared to have little effect on physical measures when applied for 5 minutes immediately after strenuous calf exercise. Given the small increase in muscle soreness up to 4 hours after their use, caution is recommended when using massage guns immediately after strenuous lower body exercise.


Asunto(s)
Armas de Fuego , Mialgia , Masculino , Adulto Joven , Humanos , Femenino , Adolescente , Adulto , Mialgia/terapia , Músculo Esquelético/fisiología , Ejercicio Físico/fisiología , Masaje
12.
Geroscience ; 46(1): 349-365, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37368157

RESUMEN

Mitochondrial improvements resulting from behavioral interventions, such as diet and exercise, are systemic and apparent across multiple tissues. Here, we test the hypothesis that factors present in serum, and therefore circulating throughout the body, can mediate changes in mitochondrial function in response to intervention. To investigate this, we used stored serum from a clinical trial comparing resistance training (RT) and RT plus caloric restriction (RT + CR) to examine effects of blood borne circulating factors on myoblasts in vitro. We report that exposure to dilute serum is sufficient to mediate bioenergetic benefits of these interventions. Additionally, serum-mediated bioenergetic changes can differentiate between interventions, recapitulate sex differences in bioenergetic responses, and is linked to improvements in physical function and inflammation. Using metabolomics, we identified circulating factors associated with changes in mitochondrial bioenergetics and the effects of interventions. This study provides new evidence that circulating factors play a role in the beneficial effects of interventions that improve healthspan among older adults. Understanding the factors that drive improvements in mitochondrial function is a key step towards predicting intervention outcomes and developing strategies to countermand systemic age-related bioenergetic decline.


Asunto(s)
Dieta , Mitocondrias , Humanos , Masculino , Femenino , Mitocondrias/metabolismo , Metabolismo Energético/fisiología , Ejercicio Físico/fisiología , Terapia por Ejercicio
13.
Br J Nutr ; 131(3): 461-473, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-37641937

RESUMEN

Rhodiola rosea (RR) is a plant whose bioactive components may function as adaptogens, thereby increasing resistance to stress and improving overall resilience. Some of these effects may influence exercise performance and adaptations. Based on studies of rodents, potential mechanisms for the ergogenic effects of RR include modulation of energy substrate stores and use, reductions in fatigue and muscle damage and altered antioxidant activity. At least sixteen investigations in humans have explored the potential ergogenicity of RR. These studies indicate acute RR supplementation (∼200 mg RR containing ∼1 % salidroside and ∼3 % rosavin, provided 60 min before exercise) may prolong time-to-exhaustion and improve time trial performance in recreationally active males and females, with limited documented benefits of chronic supplementation. Recent trials providing higher doses (∼1500 to 2400 mg RR/d for 4­30 d) have demonstrated ergogenic effects during sprints on bicycle ergometers and resistance training in trained and untrained adults. The effects of RR on muscle damage, inflammation, energy system modulation, antioxidant activity and perceived exertion are presently equivocal. Collectively, it appears that adequately dosed RR enhances dimensions of exercise performance and related outcomes for select tasks. However, the current literature does not unanimously show that RR is ergogenic. Variability in supplementation dose and duration, concentration of bioactive compounds, participant characteristics, exercise tests and statistical considerations may help explain these disparate findings. Future research should build on the longstanding use of RR and contemporary clinical trials to establish the conditions in which supplementation facilitates exercise performance and adaptations.


Asunto(s)
Sustancias para Mejorar el Rendimiento , Rhodiola , Masculino , Adulto , Femenino , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Antioxidantes/farmacología , Rhodiola/química , Sustancias para Mejorar el Rendimiento/farmacología , Ejercicio Físico/fisiología
14.
Int J Sport Nutr Exerc Metab ; 34(2): 69-78, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37922892

RESUMEN

Previous studies showed that collagen peptide supplementation along with resistance exercise enhance muscular recovery and function. Yet, the efficacy of collagen peptide supplementation in addition to standard nutritional practices in athletes remains unclear. Therefore, the objective of the study was to compare the effects of combined collagen peptide (20 g) and whey protein (25 g) supplementation with a similar daily protein dose (45 g) of whey protein alone on indices of muscle damage and recovery of muscular performance during eccentric exercise training. Young fit males participated in a 3-week training period involving unilateral eccentric exercises for the knee extensors. According to a double-blind, randomized, parallel-group design, before and after training, they received either whey protein (n = 11) or whey protein + collagen peptides (n = 11). Forty-eight hours after the first training session, maximal voluntary isometric and dynamic contraction of the knee extensors were transiently impaired by ∼10% (Ptime < .001) in whey protein and whey protein + collagen peptides, while creatine kinase levels were doubled in both groups (Ptime < .01). Furthermore, the training intervention improved countermovement jump performance and maximal voluntary dynamic contraction by respectively 8% and 10% (Ptime < .01) and increased serum procollagen type 1N-terminal peptide concentration by 10% (Ptime < .01). However, no differences were found for any of the outcomes between whey and whey protein + collagen peptides. In conclusion, substituting a portion of whey protein for collagen peptide, within a similar total protein dose, improved neither indices of eccentric muscle damage nor functional outcomes during eccentric training.


Asunto(s)
Entrenamiento de Fuerza , Suero Lácteo , Masculino , Humanos , Proteína de Suero de Leche/farmacología , Músculo Esquelético/metabolismo , Suplementos Dietéticos , Ejercicio Físico/fisiología , Péptidos/metabolismo , Péptidos/farmacología , Colágeno/metabolismo , Método Doble Ciego
15.
J Phys Act Health ; 21(2): 181-188, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37992705

RESUMEN

BACKGROUND: Investigating the effects of breaking up sedentary behavior with short bouts of Yoga and Tai-Chi on glycemic control, concentration, and well-being in healthy individuals. METHODS: In this randomized balanced incomplete block study, 15 adults (age = 26 [2.50] y, 8 females) completed 2 of 3 protocols: uninterrupted sitting (Control), sitting interrupted with 3 minutes of Yoga every 30 minutes, or with 3 minutes of Tai-Chi every 30 minutes. Protocols lasted 7.5 hours and included a standardized diet. Glucose was measured every 30 minutes with a glucometer (Abbott FreeStyle Libre). Concentration and well-being were recorded with self-reported ecological momentary assessment. Area under the curve was calculated for glucose data. Statistical analyses were performed as a hierarchical repeated-measures model. RESULTS: Glucose area under the curve for the Yoga intervention (34.55 [3.12] mmol/L) was significantly lower than the Control (38.14 [3.18] mmol/L; P < .05). There was a trend toward lower glucose in the Tai-Chi group compared with the Control, but no significant differences were found (AUCTai-Chi = 36.64 [3.11] mmol/L; P = .57). Mean concentration in all groups decreased throughout the day, with the largest decrease in the Control. Well-being for the Yoga and Control groups decreased but increased with Tai-Chi. Concentration and well-being responses were not statistically significant between intervention groups. CONCLUSIONS: Breaking up sedentary behavior using 3-minute bouts of Yoga significantly lowers blood glucose in healthy individuals without compromising concentration or well-being. Tai-Chi did not provide the same significant effect on glucose levels but allowed better maintenance of concentration and well-being. These interventions provide effective ways to combat the deleterious effects of prolonged sedentary time while maintaining concentration and well-being.


Asunto(s)
Taichi Chuan , Yoga , Adulto , Femenino , Humanos , Conducta Sedentaria , Ejercicio Físico/fisiología , Glucemia
16.
Am J Physiol Cell Physiol ; 326(1): C143-C160, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37982172

RESUMEN

Over the last decade, there has been a growing interest in the use of ketone supplements to improve athletic performance. These ketone supplements transiently elevate the concentrations of the ketone bodies acetoacetate (AcAc) and d-ß-hydroxybutyrate (ßHB) in the circulation. Early studies showed that ketone bodies can improve energetic efficiency in striated muscle compared with glucose oxidation and induce a glycogen-sparing effect during exercise. As such, most research has focused on the potential of ketone supplementation to improve athletic performance via ingestion of ketones immediately before or during exercise. However, subsequent studies generally observed no performance improvement, and particularly not under conditions that are relevant for most athletes. However, more and more studies are reporting beneficial effects when ketones are ingested after exercise. As such, the real potential of ketone supplementation may rather be in their ability to enhance postexercise recovery and training adaptations. For instance, recent studies observed that postexercise ketone supplementation (PEKS) blunts the development of overtraining symptoms, and improves sleep, muscle anabolic signaling, circulating erythropoietin levels, and skeletal muscle angiogenesis. In this review, we provide an overview of the current state-of-the-art about the impact of PEKS on aspects of exercise recovery and training adaptation, which is not only relevant for athletes but also in multiple clinical conditions. In addition, we highlight the underlying mechanisms by which PEKS may improve exercise recovery and training adaptation. This includes epigenetic effects, signaling via receptors, modulation of neurotransmitters, energy metabolism, and oxidative and anti-inflammatory pathways.


Asunto(s)
Cuerpos Cetónicos , Cetonas , Humanos , Cuerpos Cetónicos/metabolismo , Ejercicio Físico/fisiología , Ácido 3-Hidroxibutírico , Suplementos Dietéticos
17.
Int J Sport Nutr Exerc Metab ; 34(1): 30-37, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37898479

RESUMEN

Guarana (GUA) seed extract, containing caffeine (CAF) and additional bioactive compounds, may positively affect mental performance, but evidence regarding exercise is limited. This investigation assessed acute GUA ingestion compared with CAF on endurance performance. Eleven endurance-trained noncyclists and cyclists (V˙O2peak = 49.7 ± 5.9, 60.4 ± 4.6 ml·kg·min-1) completed a double-blind, crossover experiment after ingesting (a) 100 mg CAF, (b) 500 mg GUA (containing 130 mg CAF), or (c) placebo (P) prior to 60-min fixed cycling workload (FIX) + 15-min time trial. Oxygen uptake, heart rate, respiratory exchange ratio, blood glucose, and lactate were not different (p ≥ .052) during FIX. A significant interaction (p = .042) for perceived exertion was observed at 50-min FIX with lower rating (p = .023) for GUA versus CAF but not compared with P. Work accumulated over 15-min time trial was greater (p = .038) for GUA versus P due to higher early (1-11 min) work outputs. Work performance favored (effect size = 0.18; 95% confidence interval [0.003, 0.355], p = .046) GUA (241.4 ± 39.9 kJ) versus P (232.1 ± 46.6 kJ), but CAF (232.3 ± 43.9) was not different from GUA (effect size = 0.19; 95% confidence interval [-0.022, 0.410], p = .079) or P. Postexercise strength loss was not attenuated with GUA (-5.6 ± 8.5%) or CAF (-8.3 ± 9.4%) versus P (-10.3 ± 5.1%). Acute GUA ingestion improved work performance relative to P, but effects were trivial to small and unrelated to altered substrate oxidation or muscular strength. Ergogenicity may involve central mechanisms reducing perceived effort with GUA (containing 130 mg caffeine). Due to issues related to identical matching of dosage, whether GUA confers additional benefits beyond its CAF content cannot be determined at present.


Asunto(s)
Rendimiento Atlético , Paullinia , Humanos , Cafeína , Resistencia Física/fisiología , Ácido Láctico , Ejercicio Físico/fisiología , Método Doble Ciego , Estudios Cruzados , Rendimiento Atlético/fisiología
18.
J Hypertens ; 42(1): 101-108, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37728100

RESUMEN

OBJECTIVE: Prepregnancy optimization of cardiovascular function may reduce the risk of pre-eclampsia. We aimed to assess the feasibility and effect of preconception cardiovascular monitoring, exercise, and beetroot juice on cardiovascular parameters in women planning to conceive. DESIGN AND METHOD: Prospective single-site, open-label, randomized controlled trial. Thirty-two women, aged 18-45 years, were allocated into one of four arms (1 : 1 : 1 : 1): exercise, beetroot juice, exercise plus beetroot juice and no intervention for 12 weeks. Blood pressure (BP) was measured at home daily. Cardiac output ( CO ) and total peripheral resistance (TPR) were assessed via bio-impedance. RESULTS: Twenty-nine out of 32 (91%) participants completed the study. Adherence to daily BP and weight measurements were 81% and 78%, respectively ( n  = 29). Eight out of 15 (53%) of participants did not drink all the provided beetroot juice because of forgetfulness and taste. After 12 weeks, exercise was associated with a reduction in standing TPR (-278 ±â€Š0.272 dynes s cm -5 , P  < 0.05), and an increase in standing CO (+0.88 ±â€Š0.71 l/min, P  < 0.05). Exercise and beetroot juice together was associated with a reduction in standing DBP ( 7 ±â€Š6 mmHg, P  < 0.05), and an increase in standing CO (+0.49 ±â€Š0.66 l/min, P  < 0.05). The control group showed a reduction in standing TPR ( 313 ±â€Š387 dynes s cm -5 ) and standing DBP ( 8 ±â€Š5mmHg). All groups gained weight. CONCLUSION: Exercise and beetroot juice in combination showed a signal towards improving cardiovascular parameters. The control group showed improvements, indicating that home measurement devices and regular recording of parameters are interventions in themselves. Nevertheless, interventions before pregnancy to improve cardiovascular parameters may alter the occurrence of hypertensive conditions during pregnancy and require further investigation in adequately powered studies.


Asunto(s)
Hipertensión , Nitratos , Embarazo , Humanos , Femenino , Estudios Prospectivos , Presión Sanguínea , Ejercicio Físico/fisiología , Suplementos Dietéticos , Método Doble Ciego
19.
Nutrients ; 15(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38068803

RESUMEN

Iron is an essential micronutrient for athletes, intricately linked to their performance, by regulating cellular respiration and metabolism. Impaired iron levels in the body can significantly hinder athletic performance. The increased demand for iron due to exercise, coupled with potential dietary iron insufficiencies, particularly among endurance athletes, amplifies the risk of iron deficiency. Moreover, prolonged exercise can impact iron absorption, utilization, storage, and overall iron concentrations in an athlete. On the contrary, iron overload may initially lead to enhanced performance; however, chronic excess iron intake or underlying genetic conditions can lead to detrimental health consequences and may negatively impact athletic performance. Excess iron induces oxidative damage, not only compromising muscle function and recovery, but also affecting various tissues and organs in the body. This narrative review delineates the complex relationship between exercise and iron metabolism, and its profound effects on athletic performance. The article also provides guidance on managing iron intake through dietary adjustments, oral iron supplementation for performance enhancement in cases of deficiency, and strategies for addressing iron overload in athletes. Current research is focused on augmenting iron absorption by standardizing the route of administration while minimizing side effects. Additionally, there is ongoing work to identify inhibitors and activators that affect iron absorption, aiming to optimize the body's iron levels from dietary sources, supplements, and chelators. In summary, by refining the athletic diet, considering the timing and dosage of iron supplements for deficiency, and implementing chelation therapies for iron overload, we can effectively enhance athletic performance and overall well-being.


Asunto(s)
Rendimiento Atlético , Sobrecarga de Hierro , Humanos , Dieta , Ejercicio Físico/fisiología , Hierro/metabolismo , Suplementos Dietéticos , Atletas
20.
Sci Rep ; 13(1): 22644, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38114553

RESUMEN

Aerobic exercise acutely improves cognitive function (e.g., executive function (EF); memory recognition (MR)) and increases circulating brain-derived neurotrophic factor (BDNF). In addition, branched-chain amino acids (BCAA) ingestion acutely shortens the choice reaction time and increases brain BDNF. We examined whether the ingestion of essential amino acid (EAA) supplements (mainly composed of BCAA) would positively impact on cognitive function and circulating BDNF after moderate-intensity aerobic exercise. Twenty-two healthy young men received either an EAA supplements or the placebo (PL) 30 min before undergoing aerobic exercise. The participants performed a cycling exercise at 60% of peak oxygen uptake for 30 min. EF after aerobic exercise was better after the EAA treatment than after the PL treatment (P = 0.02). MR (P = 0.38 for response accuracy; P = 0.15 for reaction time) and circulating BDNF (P = 0.59) were not altered by EAA supplements. EF improvement was correlated with increases in some amino acids (leucine, isoleucine, valine, lysine, phenylalanine; all Ps < 0.05) that are potential substrates for synthesizing neurotransmitters in the brain. These results suggest that EAA supplements ingestion had a positive effect on EF after moderate-intensity aerobic exercise, while MR and BDNF were not altered.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Función Ejecutiva , Masculino , Humanos , Aminoácidos Esenciales , Aminoácidos de Cadena Ramificada , Ejercicio Físico/fisiología , Ingestión de Alimentos
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