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1.
Arch Pharm (Weinheim) ; 357(6): e2300689, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38400693

RESUMO

The phytosteroid ecdysterone is classified as an anabolic agent and has been included on the monitoring list of the World Anti-Doping Agency since 2020. Therefore, the consumption of food rich in ecdysterone, such as quinoa and spinach, is the focus of a lively debate. Thus, the urinary excretion of ecdysterone and its metabolites in humans was investigated following quinoa consumption alone and in combination with spinach. Eight participants (four male and four female) were included, and they ingested 368 ± 61 g cooked quinoa alone and in combination with 809 ± 115 g spinach after a washout. Post-administration urines were analyzed by LC-MS/MS. After intake of both preparations, ecdysterone and two metabolites were excreted in the urine. The maximum concentration of ecdysterone ranged from 0.44 to 5.5 µg/mL after quinoa and from 0.34 to 4.1 µg/mL after quinoa with spinach. The total urinary excreted amount as parent drug plus metabolites was 2.61 ± 1.1% following quinoa intake and 1.7 ± 0.9% in combination with spinach. Significant differences were found in the total urinary excreted amount of ecdysterone, 14-deoxy-ecdysterone, and 14-deoxy-poststerone. Only small portions of ecdysterone from quinoa and the combination with spinach were excreted in the urine, suggesting that both quinoa and spinach are poor sources of ecdysterone in terms of bioavailability.


Assuntos
Chenopodium quinoa , Spinacia oleracea , Chenopodium quinoa/química , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Espectrometria de Massas em Tandem , Cromatografia Líquida
2.
BMC Womens Health ; 23(1): 526, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803287

RESUMO

BACKGROUND: Resistance training (RT) is effective in counteracting the age- and menopause-related loss of muscle mass (MM) and strength in middle-aged women (40-60 years). Research on RT with free weights is limited in pre- and post-menopausal women. Based on this, a 20-week training intervention was conducted with this population to investigate the effects of systematic RT with free weights on strength capacity and body composition. METHOD: Forty-one healthy women (52.0 ± 3.6 years) participated in this study. After 10-week control phase (no RT, T0-T1) followed by a 10-week intervention phase (T1-T2) with RT twice a week and 6-8 sets of each muscle per week. Subjects were randomly assigned to a low-intensity (50% 1-RM) or moderate-intensity (75% 1-RM) RT group and divided into pre-menopausal and post-menopausal according to their hormone profile. Fat-free mass (FFM), MM, fat mass (FM), muscle thickness (Vastus lateralis (VL), Rectus femoris (RF), Triceps brachii (TB)), grip strength, 1-RM squat and bench press were assessed before and after each phase. Statistical analysis was performed using a linear mixed model to account for fixed (time and group) and random (individual) effects. RESULTS: A total of 31 women successfully completed the study. No injuries occurred during the intervention. Significant increases in 1-RM squat and bench press were observed in all groups. No interaction effect was observed for the strength parameters. In pre-menopausal women, FFM, MM and RF muscle thickness increased significantly, while VL showed a trend. These effects were not present in post-menopausal women regardless of RT intensity. CONCLUSION: RT with free weight is safe and effective for middle-aged women to increase 1-RM. Hypertrophy effects were found exclusively in pre-menopausal women. To achieve hypertrophy and/or body composition changes in post-menopausal women, larger training volumes (> 6-8 sets/muscle per week) are likely required.


Assuntos
Força Muscular , Treinamento Resistido , Pessoa de Meia-Idade , Humanos , Feminino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Composição Corporal , Menopausa , Hipertrofia
3.
Int J Sports Med ; 44(10): 692-703, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37253363

RESUMO

The use of plant steroids to improve physical health and performance is becoming increasingly popular. One of these plant steroids is diosgenin, which is mainly available in fenugreek. As a result, some studies have been conducted to improve physical health. Fenugreek extracts are also becoming increasingly popular in the context of athletic performance. Based on these assumptions, a systematic review with meta-analysis was conducted to evaluate the promoting effects of fenugreek on strength performance, body composition, and hormone concentration. Four databases were screened according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The current version of ReviewManager (RevMan) was used for the statistical evaluation. Seven studies with 449 participants (378 male, 71 female) met the inclusion criteria. A small effect of fenugreek was detected for total testosterone (standard mean difference (SMD): 0.32; 95% confidence interval (CI): 0.09 0.55), free testosterone (SMD: 0.24; 95% CI: -0.04, 0.52), lean body mass (SMD: 0.19; 95% CI: -0.10, 0.49), fat mass (SMD: -0.19; 95% CI: -0.44, 0.05), and leg press performance (SMD: 0.22; 95% CI: -0.02, 0.47), in male athletes. The meta-analysis shows that chronic application of fenugreek has performance-enhancing and anabolic effects in male athletes, but no statements can be made for female athletes.


Assuntos
Anabolizantes , Fitosteróis , Trigonella , Humanos , Anabolizantes/farmacologia , Testosterona , Atletas
4.
J Sports Sci Med ; 22(4): 778-789, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38045750

RESUMO

The purpose was to compare the electromyographic (EMG) activity of the Hang Power Clean (HPC) and Hang Power Snatch (HPS) with the Hang Clean Pull (HCP) and Hang Snatch Pull (HSP). Additionally, the influence of weightlifting expertise (beginner, advanced and elite) on EMG activity was analyzed. Twenty-seven weightlifters (beginner: n = 11, age: 23.9 ± 3.2 years, bodyweight: 75.7 ± 10.5 kg; advanced: n = 10, age: 24.8 ± 4.5 years, bodyweight: 69.4 ± 13.9 kg; elite: n = 6, age: 25.5 ± 5.2 years, bodyweight: 75.5 ± 12.5 kg) participated in this study. Participants performed two repetitions of HPC, HPS, HCP, and HSP at 50%, 70%, and 90% 1RM, respectively. The EMG activity of vastus lateralis (VL), gluteus maximus (GM), erector spinae (ES), rectus abdominis (RA) and trapezius (TZ) was recorded and normalized to the maximum voluntary isometric contraction (MVIC) of each muscle. There were significant differences in RA and ES EMG activity at 70% and 90% 1RM during HPC compared to HCP in the beginner group (p < 0.05, Hedges g = 0.50-1.06). Significant greater ES activity was observed in the beginner, advanced, and elite groups (p < 0.05, g = 0.27-0.98) during the HPS when compared to the HSP at 50-90% 1RM. TZ muscle activity was significantly greater at 50% and 70% 1RM in the HCP compared to the HPC in the elite group (p < 0.05, g = 0.61-1.08), while the beginner group reached significance only at 50% 1RM favoring HPC (p < 0.05, g = 0.38). Moreover, the EMG activity of the TZ during the HSP and HPS was significantly different only at 50% 1RM in the elite group and favored HSP (p < 0.05, g = 0.27). No differences were observed between the levels of weightlifting expertise. Based upon the results of this study, the overall pattern of EMG activity of the predominant muscles involved in HPC/HPS and the corresponding weightlifting pulling derivatives, apart from the stabilizing muscle (RA and ES), is similar at higher intensities (>70% 1RM) and expertise does not influence muscle activity.


Assuntos
Treinamento Resistido , Humanos , Adulto Jovem , Adulto , Treinamento Resistido/métodos , Músculo Esquelético/fisiologia , Músculo Quadríceps/fisiologia , Exercício Físico/fisiologia , Nádegas
5.
Arch Toxicol ; 93(7): 1807-1816, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31123801

RESUMO

Recent studies suggest that the anabolic effect of ecdysterone, a naturally occurring steroid hormone claimed to enhance physical performance, is mediated by estrogen receptor (ER) binding. In comparison with the prohibited anabolic agents (e.g., metandienone and others), ecdysterone revealed to be even more effective in a recent study performed in rats. However, scientific studies in humans are very rarely accessible. Thus, our project aimed at investigating the effects of ecdysterone-containing products on human sport exercise. A 10-week intervention study of strength training of young men (n = 46) was carried out. Different doses of ecdysterone-containing supplements have been administered during the study to evaluate the performance-enhancing effect. Analysis of blood and urine samples for ecdysterone and potential biomarkers of performance enhancement has been conducted. To ensure the specificity of the effects measured, a comprehensive screening for prohibited performance-enhancing substances was also carried out. Furthermore, the administered supplement has been tested for the absence of anabolic steroid contaminations prior to administration. Significantly higher increases in muscle mass were observed in those participants that were dosed with ecdysterone. The same hypertrophic effects were also detected in vitro in C2C12 myotubes. Even more relevant with respect to sports performance, significantly more pronounced increases in one-repetition bench press performance were observed. No increase in biomarkers for liver or kidney toxicity was noticed. These data underline the effectivity of an ecdysterone supplementation with respect to sports performance. Our results strongly suggest the inclusion of ecdysterone in the list of prohibited substances and methods in sports in class S1.2 "other anabolic agents".


Assuntos
Anabolizantes/farmacologia , Suplementos Nutricionais , Ecdisterona/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Adulto , Anabolizantes/administração & dosagem , Animais , Desempenho Atlético/fisiologia , Biomarcadores/metabolismo , Linhagem Celular , Método Duplo-Cego , Ecdisterona/administração & dosagem , Humanos , Masculino , Camundongos , Mioblastos/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/administração & dosagem , Treinamento Resistido , Adulto Jovem
6.
Eur J Appl Physiol ; 119(4): 913-920, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30666411

RESUMO

PURPOSE: Weight lifting training has gained much popularity in recent years and is frequently used in non-professional and professional settings. However, little is known about the acute effects of a highly intensive weight lifting exercise (clean and jerk) on the hemodynamic reaction. METHODS: 18 non-professional experienced weight lifters were recruited. Hemodynamic parameters were obtained and measured at baseline (T1), after warming up (T2), and after a highly intensive clean and jerk exercise (90-95% of personal best; T3). Further, 15 (T4), and 30 min (T5) post-exercise measurements were conducted. Evaluated parameters were heart rate (HR) (b/min), peripheral and central systolic and diastolic blood pressure (pSysBP, pDiaBP, cSysBP, cDiaBP) (mmHg), pulse wave velocity (PWV) (m/s), and double product (DP). RESULTS: All hemodynamic values increased from T1 up to T3 with significantly higher values measured at T3 compared to T1 and T2. Values of measured parameters at T3 were as follows: HR: 94.4 ± 15.6 b/min, pSysBP: 147.1 ± 15.9 mmHg, pDiaBP: 87.4 ± 12.2 mmHg, cSysBP: 129.3 ± 13.8 mmHg, cDiaBP: 89.9 ± 12.8 mmHg, and: 5.8 ± 0.5 m/s, DP: 14053 ± 3669. Post-exercise (T4, T5), all values returned to baseline levels. CONCLUSIONS: Results indicate that a highly intensive weight lifting exercise led to an acute increase of blood pressure and an acute stiffening of the arteries. Yet, increases were moderate and did not reach disproportionately high levels and returned to baseline levels within 15 min post-exercise. Hence, no negative acute effects of a maximum weight lifting exercise on the hemodynamic system are observed.


Assuntos
Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Rigidez Vascular/fisiologia , Levantamento de Peso/fisiologia , Adulto , Determinação da Pressão Arterial/métodos , Teste de Esforço/métodos , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Masculino , Análise de Onda de Pulso/métodos , Adulto Jovem
8.
Front Sports Act Living ; 6: 1346637, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38746828

RESUMO

Introduction: Demographic changes are resulting in a continual increase in the proportion of individuals over 65 years old. Simultaneously, muscle mass (MM) tends to decrease with age, with a decline noticeable from the middle of the fourth decade of life. While physical activity is considered a modulator for maintaining MM, the interaction with nutrient uptake, especially protein intake, is getting more into focus. Due to a lack of data on the effect of a high-protein diet on middle-aged individuals (40-65 years), this study aimed to investigate the influence of a high-protein diet in middle-aged physically active persons on body composition and performance. Methods: Using stratified randomization, participants were allocated to either a high-protein group (>2.3 g/kg FFM/day) (n = 12, age = 57.83 ± 7.74 years, height = 170.42 cm ± 11.04 cm, BMI = 30.26 ± 4.46, MM = 31.71 ± 6.89 kg) or a control group (<2.3 g/kg/FFM/day) (n = 14, age = 58.21 ± 6.44 years, height = 170.57 cm ± 8.28 cm, BMI = 26.31 ± 5.59, MM = 29.67 ± 8.08 kg). Body composition [fat-free mass (FFM), fat mass (FM), MM] and strength were assessed at baseline (T0), after four weeks (T1) and after eight weeks (T2). Exercise habits were not changed over the entire period and dietary habits were recorded using FDDB Explorer. Statistical analysis was performed using the current version of R and linear mixed models. Results: No significant differences in energy intake were found between the groups (p = .974). In macronutrient distribution, a significantly higher consumption of protein was found in the high-protein group (p < .0001, d = 2.22) [140 ± 70 g/day (HPG) vs. 79 ± 40 g/day (CG)]. A trivial reduction in FM over time in both groups (p = .046, d = 0.04, Δt=-.83±1.60kg) was observed. No significant differences were detected in FFM (p = .887) and MM (p = .711). Trivial interaction effects (time*group) were observed for upper (p = .007, d = 0.12, ΔHPG = 4.38 ± 3.25 kg) and lower body strength (p = .0507, d = 0.07, ΔHPG = 3.33 ± 2.36 kg). Discussion: Our results indicate no to only trivial effects of adding a high-protein diet to otherwise physically active middle-aged individuals. Trivial effects could be seen for an increase in muscle strength after this eight-week intervention. However, MM and FFM were not significantly affected. Based on the small effect sizes we observed in our results we do not see a benefit of a high-protein diet on body composition and strength capacity without altering the exercise habits.

9.
J Nutr Health Aging ; 28(10): 100349, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39232439

RESUMO

BACKGROUND: Menopause has a significant impact on the endocrine system of middle-aged women, resulting in a loss of skeletal muscle mass (SMM), changes in fat mass (FM) and a reduction in strength capacity. Resistance training (RT) and a high-protein diet (HPD) are effective methods for maintaining or increasing SMM. This study aims to determine the effects of HPD and RT on body composition, muscle thickness and strength capacity in postmenopausal women. METHODS: In total 55 healthy postmenopausal women (age: 58.2 ± 5.6 years, weight 69.1 ± 9.6 kg, height 166.5 ± 6.5 cm) successfully participated in the study. The women were randomly assigned to either group: training + protein (2.5 g/kg fat-free mass (FFM)) (n = 15; TP); only training (n = 12; T); only protein (2.5 g/kg FFM) (n = 14; CP) or control (n = 14; C). TP and T performed RT for 12 weeks with three training sessions and five exercises each. CP and C were prohibited from training during the period. The main parameters analysed for body composition were FFM, SMM, FM, muscle thickness of the M. rectus femoris, M. biceps femoris, M. triceps brachii and M. biceps brachii muscles. Strength was tested using a dynamometer for grip strength and 1-RM in the squat (BBS) and deadlift (DL). RESULTS: The SMM significantly increased by RT (TP: (Δ+1.4 ± 0.9 kg; p < 0.05; d = 0.4; T: Δ+1.2 ± 1.3kg; p < 0.05; d = 0.3) and FM could be reduced only in T: (Δ-2.4 ± 2.9 kg; p < 0.05; d = 0.3). In muscle thickness a significant increase in the M. biceps brachii in both training groups (TP: (Δ+0.4 ± 0.3 cm; p < 0.05; d = 1.6; T: (Δ+0.3 ± 0.3 cm; p < 0.05; d = 0.9) and in M. biceps femoris only in TP (Δ+0.3 ± 0.4 cm; p < 0.05; d = 0.9) were observed. HPD without training does not affect body composition, A significant increase in grip strength (TP: Δ+4.7 ± 2.4 kg; (p < 0.05; d = 1.5; T: (Δ+3.6 ± 3.0 kg; p < 0.05; d = 0.8), in BBS (TP: (Δ+30.0 ± 14.2 kg; p < 0.05; d = 1.5; T: (Δ+34.0 ± 12.0 kg; p < 0.05; d = 2.4) and in DL (TP: (Δ+20.8 ± 10.3 kg; p < 0.05; d = 1.6; T: (Δ+22.1 ± 7.6 kg; p < 0.05; d = 2.0) was observed in both training groups. The CP also recorded a significant increase in the BBS (Δ+7.5 ± 5.4 kg; p < 0.05; d = 0.4) and in DL (Δ+5.5 ± 7.7 kg; p < 0.05; d = 0.5). No significant differences were detected for TP and T for any of the parameters. CONCLUSION: The results indicate that RT enhances body composition and strength capacity in postmenopausal women and is a preventive strategy against muscle atrophy. Besides HPD without training has a trivial significant effect on BBS and DL. HPD with RT has no clear additive effect on body composition and strength capacity. Further studies are needed to confirm these observations.

10.
Nutrients ; 16(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38337659

RESUMO

BACKGROUND: The consumption of dietary supplements (DS) is widespread among the general population and competitive athletes. However, only a few competitive athletes seek information from experts about the effects and use of DS. Furthermore, it is currently unknown whether certain sports have a higher affinity for DS than others. METHODS: This study aimed to identify differences between different sports categories and subgroups that may have a very high affinity for DS. For this purpose, competitive athletes were surveyed. The survey included the type of sport, the training frequency, the number of competitions, the consumption behaviour of five DS categories (general health, regeneration promotion, performance enhancement, booster, and weight loss) as well as personal data such as biological sex and age. Subsequently, correlations, configural frequencies (CFA), and multiple correspondence analyses (MCA) were used to identify subgroups with a high affinity of consumption behaviour. RESULTS: A total of 409 questionnaires could be evaluated. It was found that all DS categories except weight loss were related. In addition, it was observed that in sports from the power category and from the endurance category, there was even higher consumption behaviour than in other sports categories. Male power athletes in particular have a higher affinity for consuming DS than other subgroups. CONCLUSIONS: This study shows that there is a clear different consumption behaviour depending on the type of sport. Male power athletes in particular are the subgroup with the greatest consumption behaviour and therefore require special education on the effects and use of DS. This subgroup in particular should receive increased attention in counselling on DS to minimise the possible risks of DS use.


Assuntos
Dopagem Esportivo , Esportes , Humanos , Masculino , Suplementos Nutricionais , Atletas , Redução de Peso
11.
J Int Soc Sports Nutr ; 21(1): 2337252, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38572744

RESUMO

BACKGROUND: Rapid regeneration after intense exercise is essential for competitive athletes. Based on this assumption, supplementation strategies, focusing on food supplements, are increasing to improve the recovery processes. One such supplement is cannabidiol (CBD) which is gaining more attention in competitive sports. However, the evidence is still lacking and there are no data available about the effect of a short-term chronic application. METHODS: A three-arm double-blind cross-over study was conducted to determine the effects of two different CBD products on performance, muscle damage and inflammatory processes in well-trained athletes. In total 17 subjects took successfully part in this study. Each subject underwent the six-day, high-intensity training protocol three times. After each training session, each subject took either a placebo or a CBD product (60 mg of oil or solubilisate). Between the intervention phases, at least four weeks of washout period was conducted. Before and after the training protocols the performance capacity in countermovement jump (CMJ), back squat (BS), bench press (BP) and 1-mile run were measured and biomarkers for muscle damage (creatine kinase, myoglobin), inflammatory processes (interleukin 6 and 10) and immune cell activity (ratios of neutrophil granulocytes, lymphocytes and, platelets) were analyzed. For statistical analyses, the current version of R and a linear mixed model was used. RESULTS: It could identify different effects of the training protocol depending on performance level (advanced or highly advanced athletes) (p < .05). Regardless of the performance level, muscle damage and a reduction in performance could be induced by the training protocol. Only CBD oil was associated with a reduction in myoglobin concentration (p < .05) in advanced athletes. Concerning immune activity, a significant decrease in platelets lymphocyte ratios was observed in advanced athletes after placebo treatment (p < .05). CBD oil application showed a slight inhibitory effect (p < .10). Moreover, the reduction in performance differs between the performance levels. A significant decrease in CMJ was observed in advanced athletes and a decreasing trend in BS was observed in highly advanced athletes after placebo treatment (p < 0.10). Both CBD products do not affect performance parameters. For inflammatory parameters, no effects were observed. CONCLUSION: It was found that the performance level of the subjects was a decisive factor and that they responded differently to the training protocol and the CBD application. However, no clear effects of either CBD product were found and further research is needed to identify the long-term effects of CBD application.


Assuntos
Canabidiol , Esportes , Humanos , Estudos Cross-Over , Canabidiol/farmacologia , Mioglobina , Músculo Esquelético , Atletas , Método Duplo-Cego , Suplementos Nutricionais , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Nutrients ; 16(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38794667

RESUMO

BACKGROUND: Various nutritional strategies are increasingly used in sports to reduce oxidative stress and promote recovery. Chokeberry is rich in polyphenols and can reduce oxidative stress. Consequently, chokeberry juices and mixed juices with chokeberry content are increasingly used in sports. However, the data are very limited. Therefore, this study investigates the effects of the short-term supplementation of a red fruit juice drink with chokeberry content or a placebo on muscle damage, oxidative status, and leg strength during a six-day intense endurance protocol. METHODS: Eighteen recreational endurance athletes participated in a cross-over high intensity interval training (HIIT) design, receiving either juice or a placebo. Baseline and post-exercise assessments included blood samples, anthropometric data, and leg strength measurements. RESULTS: A significant increase was measured in muscle damage following the endurance protocol in all participants (∆ CK juice: 117.12 ± 191.75 U/L, ∆ CK placebo: 164.35 ± 267.00 U/L; p = 0.001, η2 = 0.17). No group effects were detected in exercise-induced muscle damage (p = 0.371, η2 = 0.010) and oxidative status (p = 0.632, η2 = 0.000). The reduction in strength was stronger in the placebo group, but group effects are missing statistical significance (∆ e1RM juice: 1.34 ± 9.26 kg, ∆ e1RM placebo: -3.33 ± 11.49 kg; p = 0.988, η2 = 0.000). CONCLUSION: Although a reduction in strength can be interpreted for the placebo treatment, no statistically significant influence of chokeberry could be determined. It appears that potential effects may only occur with prolonged application and a higher content of polyphenols, but further research is needed to confirm this.


Assuntos
Atletas , Estudos Cross-Over , Sucos de Frutas e Vegetais , Força Muscular , Resistência Física , Polifenóis , Humanos , Polifenóis/farmacologia , Masculino , Adulto , Força Muscular/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Adulto Jovem , Feminino , Estresse Oxidativo/efeitos dos fármacos , Perna (Membro)/fisiologia , Método Duplo-Cego , Frutas/química , Photinia/química , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Músculo Esquelético/metabolismo , Exercício Físico/fisiologia , Treino Aeróbico/métodos
13.
Artigo em Inglês | MEDLINE | ID: mdl-36767221

RESUMO

Over the past few years, the number of people who have avoided animal products has been rising steadily. A plant-based diet is associated with a healthier lifestyle and has positive effects on various diseases. More and more healthy active people and performance-orientated athletes are giving up animal products for various reasons, such as for an improved performance or faster regeneration. However, the data in this context are limited. This study aimed to obtain initial findings on the influence of a diet change to veganism on the performance of strength-trained individuals. For this study, a total of 15 omnivorous individuals were recruited. They documented their dietary food intakes over 16 weeks. Every four weeks, the strength performance was tested via a leg press and bench press. In the first 8 weeks, the participants maintained their omnivorous diet, followed by 8 weeks of a vegan dietary phase. In total, 10 subjects participated successfully, and their data were part of the statistical analyses. There was no difference in the absolute and relative strength performance for the leg and bench press after changing to a vegan diet. For the total calorie intake and carbohydrates, only a small treatment effect, but no time effect, was observed. However, for the protein intake, a time and group effect were detected. In addition, the relative protein intake decreased significantly and was lower than the current recommendations for athletes. The results demonstrate that a change to a vegan diet has no beneficial nor negative effect on the strength performance when the total calorie intake and carbohydrate content are covered in the first 8 weeks.


Assuntos
Dieta Vegana , Dieta , Animais , Humanos , Projetos Piloto , Ingestão de Energia , Veganos
14.
PLoS One ; 18(4): e0284216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37053143

RESUMO

BACKGROUND: Women are underrepresented in resistance exercise-related studies. To date only one meta-analysis provides concrete training recommendations for muscle strength gains through resistance training in eumenorrhoeic women. OBJECTIVE: This review aims to identify research gaps to advance future study in this area to expand the knowledge concerning resistance exercise-induced strength gains in women and to provide guidelines on the number of repetitions per set and the training frequency per week to enhance maximal muscle strength. METHODS: The electronic databases PubMed and Web of Science were searched using a comprehensive list of relevant terms. After checking for exclusion criteria, 31 studies could be included in the final analysis using data from 621 subjects. From these data sets, the ideal number of repetitions per set and also the training frequency per week were analyzed. RESULTS: In the lower body, the largest gains were achieved with 1 to 6 repetitions (17.4% 1RM increase). For lower-body exercises, the highest gains were achieved with 13 to 20 repetitions (8.7% 1RM increase). The lower body should be trained two times a week (8.5% 1RM increase). The upper body should be trained two (5.2% 1RM increase) to three times (4.5% 1RM increase) a week. CONCLUSION: Women can increase their 1RM by 7.2% per week in the upper body and by 5.2% per week in the lower-body exercises. The upper body can be trained more than two times per week whereas the lower body should be trained two times. Women with intermediate experiences in RT and advanced performance level show more rapid increases in strength in the lower-body compared to the upper-body while no differences were found between upper and lower limb adaptations in RT-beginner subjects.


Assuntos
Treinamento Resistido , Humanos , Feminino , Músculo Esquelético/fisiologia , Força Muscular/fisiologia , Exercício Físico , Adaptação Fisiológica
15.
Mol Nutr Food Res ; 67(14): e2200518, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37161586

RESUMO

SCOPE: The phytosteroid ecdysterone is present in spinach. In this study, the urinary elimination of ecdysterone and its metabolites in humans is investigated following spinach consumption of two different culinary preparations. METHODS AND RESULTS: Eight participants (four males, four females) ingested 950 (27.1) g sautéed spinach (average [±standard deviation (SD)]) and 912 (70.6) g spinach smoothie as second intervention after washout. Post-administration urines are analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). After intake of both preparations, ecdysterone and two metabolites, 14-deoxy-ecdysterone, and 14-deoxy-poststerone, are excreted in urine. The maximum concentration of ecdysterone is ranging from 0.09 to 0.41 µg mL-1 after sautéed spinach and 0.08-0.74 µg mL-1 after smoothie ingestion. The total excreted amount (mean% [±SD]) in the urine as a parent drug plus the metabolites is only 1.4 (1.0) for both sautéed spinach and smoothie. The apparent sex related differences in 14-deoxy-poststerone excretion will need further investigations. CONCLUSION: Only a small proportion of ecdysterone from spinach is excreted into urine. No significant differences are found in concentration and recovered amount (%) of ecdysterone, 14-deoxy-ecdysterone, and 14-deoxy-poststerone in urine between sautéed spinach and smoothie ingestion. A discrimination between ecdysterone from food or preparations will be challenging based on urinary concentrations only, at least for later post-administration samples.


Assuntos
Spinacia oleracea , Espectrometria de Massas em Tandem , Masculino , Feminino , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Ecdisterona/urina
16.
Front Nutr ; 9: 817724, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356737

RESUMO

Introduction: Physical training can improve several health variables in patients with type 2 diabetes mellitus (T2DM). A growing body of studies also finds a positive influence of dietary supplement (DS) intake. The aim of this review is to shed light on the possible effects of training interventions combined with DS intake in T2DM patients. Methods: A systematic search was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in the PubMed and BISp Surf databases. Inclusion criteria were defined using the Patient-Intervention-Comparison-Outcome (PICO) scheme. The Physiotherapy Evidence Database (PEDro) scale was used for quality assessment and risk of bias analysis. Results: Ten controlled interventional studies with a total number of 643 subjects met the inclusion criteria. These studies investigated the effects of (a) vitamin D (VD), (b) VD + whey protein, (c) polyphenol containing antioxidant capsules, (d) creatine, (e) L-arginine, (f) leucine-rich amino acids, and (g) broccoli sprouts powder. Eight studies investigated effects on one or more of the following health outcomes: body mass index, fat mass, insulin resistance, glycemic control, lipid profile, oxidative stress/antioxidative capacity and/or inflammatory markers/molecules. Five of the studies show clear superior effects of physical training combined with DS intake (supplements a, b, c, e) on some of these variables compared with training only. However, one study indicates that VD intake might attenuate the training effects on triglyceride levels. Another study found that training + VD + whey protein intake increased tumor necrosis factor-α levels in T2DM patients. The effects of training combined with DS intake on renal function (supplement d) or incretin metabolism (supplement a) were investigated in two further studies. These studies do not show any additional effects of DS intake. The quality of the majority of the studies was high. Conclusion: DS intake can potentially increase the benefits of physical training for specific health outcomes in T2DM patients. However, negative effects can also be observed. Possible cellular and molecular mechanisms behind potential synergistic or divergent effects of exercise training and DS use in T2DM should be explored in detail in future studies for the development of safe recommendations.

17.
Nutrients ; 13(9)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34578999

RESUMO

The number of people suffering from being overweight or obese has risen steadily in recent years. Consequently, new forms of nutrition and diets were developed as potential solutions. In the last years, the time-restricted feeding and continuous energy restriction via macronutrient-based diets were increasingly popular. Both diets were exclusively studied separately. A comparison of the two diets for people with a high body mass index despite regular physical activity has not yet been studied in detail. Therefore, this study aimed to compare the effects of these two diets on body composition and adherence. For this study, a total of 42 subjects (m = 21, f = 21) with a BMI above 25 were recruited from a local fitness gym. After a two-week familiarisation period, one of the two diets was followed over 14 weeks. Dietary behaviour was monitored throughout the period with a food diary. The primary measurement parameters were body weight, lean body mass, fat mass, body mass index, and waist and hip circumference. In addition, adherence was assessed and calculated by food diary and questionnaire. In total, the data of 35 participants (m = 14, f = 21) were analysed. Significant reductions in body weight, fat mass, body mass index, and waist and hip circumference were observed in both groups (p < 0.05). No significant change could be observed in lean body mass in either category. No group and gender differences were detected in any of the primary parameters. For the secondary parameters, a significantly higher adherence was observed in the time-restricted feeding group (p < 0.05). In addition, it can be assumed that an adherence of 60-70% cannot lead to positive changes in body composition. In conclusion, there were no differences between the two diets on the primary parameters. However, it seemed that time-restricted feeding can be better implemented in everyday life, and an adherence of more than 70% is required for both diets to prove effective.


Assuntos
Composição Corporal , Exercício Físico , Jejum , Nutrientes/administração & dosagem , Obesidade/dietoterapia , Adulto , Índice de Massa Corporal , Inquéritos sobre Dietas , Dieta Redutora , Feminino , Humanos , Masculino , Estado Nutricional , Sobrepeso/dietoterapia , Adulto Jovem
18.
Nutrients ; 13(9)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34578906

RESUMO

Cannabidiol supplements (CBD) are increasingly consumed by athletes to improve regeneration. However, the evidence for the pro-regenerative effects of CBD in sports is quite limited. Therefore, our aim was to investigate the effects of a single CBD supplementation in a six-arm placebo-controlled crossover study after resistance training on performance and muscle damage. Before and after the resistance training, one-repetition maximum in the back squat (1RM BS), countermovement jump (CMJ), and blood serum concentrations of creatine kinase (CK) and myoglobin (Myo) were measured in healthy, well-trained participants. 16 out of 21 participants completed the study and were included in the analysis. In 1RM BS, a significant decrease was observed after 24 h (p < 0.01) but not after 48 and 72 h. A significant group difference was detected after 72 h (p < 0.05; ES = 0.371). In CMJ, no significant changes were observed. The CK and Myo concentrations increased significantly after 24 h (CK: p < 0.001; Myo: p < 0.01), 48 h (CK: p < 0.001; Myo: p < 0.01) and 72 h (CK: p < 0.001; Myo: p < 0.001). After 72 h, significant group differences were observed for both muscle damage biomarkers (CK: p < 0.05 ES = 0.24; Myo: p < 0.05; ES = 0.21). The results show small but significant effects on muscle damage and recovery of squat performance after 72 h. However, more data are required for clearer statements concerning potential pro-regenerative effects of CBD supplementation after resistance training.


Assuntos
Canabidiol/farmacologia , Força Muscular/efeitos dos fármacos , Força Muscular/fisiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto , Canabidiol/administração & dosagem , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Alemanha , Humanos , Masculino , Valores de Referência , Adulto Jovem
19.
Basic Clin Androl ; 31(1): 32, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34937544

RESUMO

BACKGROUND: Hormones like testosterone play a crucial role in performance enhancement and muscle growth. Therefore, various attempts to increase testosterone release and testosterone concentration have been made, especially in the context of resistance training. Among practitioners, sexual activity (coitus and masturbation) a few hours before training is often discussed to result in increases of testosterone concentration and thus promote muscle growth. However, there is no evidence to support this assumption and the kinetics of the testosterone and cortisol response after sexual activity have not been adequately investigated. Therefore, the aim of this pilot-study was to examine the kinetics of hormone concentrations of total testosterone, free testosterone and cortisol and their ratios after masturbation. In a three-arm single blinded cross-over study, the effects of masturbation with visual stimulus were compared to a visual stimulus without masturbation and the natural kinetics in healthy young men. RESULTS: The results showed a significant between-condition difference in free testosterone concentrations. Masturbation (p < 0.01) and a visual stimulus (p < 0.05) may seem to counteract the circadian drop of free testosterone concentrations over the day. However, no statistical change was observed in the ratios between total testosterone, free testosterone and cortisol. CONCLUSIONS: It can be assumed that masturbation may have a potential effect on free testosterone concentrations but not on hormonal ratios. However, additional studies with larger sample sizes are needed to validate these findings.


RéSUMé: CONTEXTE: Les hormones comme la testostérone jouent un rôle crucial dans l'amélioration des performances et dans la croissance musculaire. Par conséquent, diverses tentatives pour augmenter la libération de testostérone et la concentration de testostérone ont été faites, en particulier dans le contexte de l'entraînement à la résistance. Chez les praticiens, l'activité sexuelle (le coït et la masturbation) quelques heures avant l'entraînement est souvent évoquée comme induisant une augmentation de la concentration de testostérone et favorisant ainsi la croissance musculaire. Il n'existe, cependant, aucune preuve à l'appui de cette hypothèse et la cinétique de la réponse de la testostérone et du cortisol après l'activité sexuelle n'a pas été étudiée de manière adéquate. Par conséquent, l'objectif de cette étude pilote était d'examiner la cinétique des concentrations hormonales de testostérone totale, de testostérone libre et de cortisol et de leurs ratios après la masturbation. Dans une étude croisée à trois bras en simple aveugle, les effets de la masturbation avec stimulus visuel ont été comparés à un stimulus visuel sans masturbation et à la cinétique naturelle chez des hommes jeunes en bonne santé. RéSULTATS: Les résultats ont montré, pour les concentrations de testostérone libre, une différence significative entre les conditions. La masturbation (p < 0,01) et un stimulus visuel (p < 0,05) pourraient sembler contrecarrer la baisse circadienne des concentrations de testostérone libre au cours de la journée. Cependant, aucun changement statistique n'a été observé dans les ratios entre la testostérone totale, la testostérone libre et le cortisol. CONCLUSION: On peut supposer que la masturbation peut avoir un effet potentiel sur la testostérone libre mais pas sur les ratios hormonaux. D'autres études, avec des échantillons de plus grande taille, sont cependant nécessaires pour valider ces résultats.

20.
Metabolites ; 11(6)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34207569

RESUMO

Ecdysterone is a phytosteroid widely discussed for its various pharmacological, growth-promoting, and anabolic effects, mediated by the activation of estrogen receptor beta (ERbeta). Performance-enhancement in sports was demonstrated recently, and ecdysterone was consequently included in the Monitoring Program, to detect potential patterns of misuse in sport. Only few studies on the pharmacokinetics of ecdysterone in humans have been reported so far. In this study, post-administration urine samples in twelve volunteers (single dose of 50 mg of ecdysterone) were analyzed using dilute-and-inject liquid-chromatography-tandem mass spectrometry. Identification and quantitation of ecdysterone and of two metabolites, 14-deoxy-ecdysterone and 14-deoxy-poststerone, was achieved. Ecdysterone was the most abundant analyte present in post-administration urine samples, detected for more than 2 days, with a maximum concentration (Cmax) in the 2.8-8.5 h urine (Cmax = 4.4-30.0 µg/mL). The metabolites 14-deoxy-ecdysterone and 14-deoxy-poststerone were detected later, reaching the maximum concentrations at 8.5-39.5 h (Cmax = 0.1-6.0 µg/mL) and 23.3-41.3 h (Cmax = 0.1-1.5 µg/mL), respectively. Sex-specific differences were not observed. Cumulative urinary excretion yielded average values of 18%, 2.3%, and 1.5% for ecdysterone, 14-deoxy-ecdysterone, and 14-deoxy-poststerone, respectively. Ecdysterone and 14-deoxy-ecdysterone were excreted following first-order kinetics with half-lives calculated with three hours, while pharmacokinetics of 14-deoxy-poststerone needs further evaluation.

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