Journal of the International Society of Sports Nutrition最新文献

{"title":"Effects of acute beetroot juice intake on performance, maximal oxygen uptake, and ventilatory efficiency in well-trained master rowers: a randomized, double-blinded crossover study.","authors":"Manuel V Garnacho-Castaño, Eulogio Pleguezuelos-Cobo, Marina Berbel, Alfredo Irurtia, Marta Carrasco-Marginet, Jorge Castizo-Olier, Pablo Veiga-Herreros, Marcos Faundez-Zanuy, Noemí Serra-Payá","doi":"10.1080/15502783.2024.2373170","DOIUrl":"10.1080/15502783.2024.2373170","url":null,"abstract":"<p><strong>Background: </strong>Beetroot juice (BRJ) intake has been considered a practical nutritional strategy among well-trained athletes. This study aimed to assess the effects of BRJ intake on performance, cardiorespiratory and metabolic variables during a simulated 2000-meter rowing ergometer test in well-trained master rowers.</p><p><strong>Method: </strong>Ten well-trained male master rowers (30-48 years) participated in a randomized, double-blind, crossover design for 3 weeks. In the first week, a researcher explained all the experimental procedures to the participants. In the next two weeks, the participants were tested in 2 rowing ergometer sessions, separated from each other by a 7-day washout period. In both strictly identical sessions, the participants randomly drank BRJ or placebo (PL) 3 hours before the start of the tests. Subsequently, the participants carried out the 2000-meter rowing ergometer tests. Oxygen saturation and blood lactate measurements were performed before starting (pretest) and at the end of the test (posttest). Performance parameters and cardiorespiratory variables were recorded during the rowing ergometer test.</p><p><strong>Results: </strong>An improvement in time trial performance was observed, with a mean difference of 4 seconds (90% confidence limits ± 3.10; <i>p</i> ≤ 0.05) compared to PL. Relative and absolute <math><mi>maximaloxygenuptake</mi><mfenced><mrow><mover><mi>V</mi><mo>˙</mo></mover><mrow><msub><mrow><mrow><mi>O</mi></mrow></mrow><mrow><mn>2</mn><mo>max</mo></mrow></msub></mrow></mrow></mfenced></math> increased (mean difference of 2.10 mL·kg^-1·min^-1, 90% confidence limits ± 1.80; mean difference of 0.16 L·min^-1 90% confidence limits ± 0.11, respectively; <i>p</i> ≤ 0.05) compared to PL. No ergogenic effect was observed on ventilatory efficiency and blood lactate concentrations after BRJ intake.</p><p><strong>Conclusion: </strong>Acute BRJ intake may improve time trial performance as well as <math><mover><mi>V</mi><mo>˙</mo></mover><mrow><msub><mrow><mrow><mi>O</mi></mrow></mrow><mrow><mn>2</mn><mo>max</mo></mrow></msub></mrow></math> in well-trained master rowers. However, BRJ does not appear to improve ventilatory efficiency.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2373170"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11221466/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141492437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutritional perspectives in female soccer: a scoping review.","authors":"Diogo V Martinho, Adam Field, Robert Naughton, Alex S Ribeiro, André Rebelo, Élvio R Gouveia, Hugo Sarmento","doi":"10.1080/15502783.2024.2366427","DOIUrl":"10.1080/15502783.2024.2366427","url":null,"abstract":"<p><strong>Background: </strong>The purpose of the review was to evaluate the literature exploring nutritional habits and practices in female soccer players.</p><p><strong>Methods: </strong>The PRISMA-ScR Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews were followed. Searches of Web of Science, PubMed and Scopus databases were conducted for studies exploring the nutritional habits and practices of female soccer players.</p><p><strong>Results: </strong>A total of 72 studies were included in the scoping review. Studies on female soccer players mainly focused on daily energy expenditure, daily energy and macronutrient intake and hydration status. A negative energy balance was consistent across studies, and the ingestion of CHO appears below the current recommendations. Female soccer players are predominately in negative energy balance, which may indicate that they are at risk of low energy availability. A high use of nutritional supplements is apparent in female soccer, whilst a large proportion of players commence training dehydrated.</p><p><strong>Conclusions: </strong>The current findings have implications for practitioners relating to the planning, management, monitoring, and implementation of nutritional intake and training and competition schedules.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2366427"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11225636/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141498334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of the ketogenic diet on resistance training load management: a repeated-measures clinical trial in trained participants.","authors":"Salvador Vargas-Molina, Manuel García-Sillero, Diego A Bonilla, Jorge L Petro, Jerónimo García-Romero, Javier Benítez-Porres","doi":"10.1080/15502783.2024.2306308","DOIUrl":"10.1080/15502783.2024.2306308","url":null,"abstract":"<p><strong>Background: </strong>The effect of low-carbohydrate high-fat dietary manipulation, such as the ketogenic diet (KD), on muscle strength assessment in resistance-training (RT) participants has focused on the one-repetition maximum test (1-RM). However, a pre-specified 1-RM value during an exercise training program disregards several confounding factors (i.e. sleep, diet, and training-induced fatigue) that affect the exerciser's \"true\" load and daily preparedness. We aimed to evaluate the effect of a 6-week RT program on load control-related variables in trained subjects following a KD intervention.</p><p><strong>Methods: </strong>Fourteen resistance-trained individuals (3F, 11 M; 30.1 [6.2] years; 174.2 [7.6] cm; 75.7 [10.8] kg; BMI 24.8 [2.1] kg·m^-2) completed this single-arm repeated-measures clinical trial. Load management variables included volume load, number of repetitions, perceived exertion (RPE), movement velocity loss, and exertion index. These primary outcomes were assessed weekly before, during, and at the end of a 6-week RT program that included traditional RT exercises (bench press, femoral lying down, lat pulldown, leg extension, and back squat).</p><p><strong>Results: </strong>There was a significant difference in RPE between weeks (<i>p</i> = 0.015, W = 0.19) with a slight trend in decreasing RPE. We found differences in the volume load per week (<i>p</i> < 0.001; W = 0.73 and <i>p</i> < 0.001, W = 0.81, respectively), with an increase in the last weeks. In the control of the load based on movement velocity, we did not find significant differences between weeks (<i>p</i> = 0.591, W = 0.06), although significant differences were found in the effort index (<i>p</i> = 0.026, W = 0.17).</p><p><strong>Conclusions: </strong>A KD diet in recreational strength participants does not appear to lead to performance losses during a RT program aimed at improving body composition. However, the lack of adherence and familiarity with the ketogenic diet must be considered specially during first weeks.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2306308"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10826788/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139576137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of pre-exercise glycerol supplementation on dehydration, metabolic, kinematic, and thermographic variables in international race walkers.","authors":"Francisco Javier Martínez-Noguera, Alessio Cabizosu, Pedro E Alcaraz, Cristian Marín-Pagán","doi":"10.1080/15502783.2024.2346563","DOIUrl":"10.1080/15502783.2024.2346563","url":null,"abstract":"<p><strong>Background: </strong>Due to the increase in global temperature, it is necessary to investigate solutions so that athletes competing in hot conditions can perform in optimal conditions avoiding loss of performance and health problems. Therefore, this study aims to evaluate the effect of pre-exercise glycerol supplementation during a rectangular test at ambient temperature mid (28.2ºC) on dehydration variables in international race walkers.</p><p><strong>Methods: </strong>Eight international male race walkers (age: 28.0 years (4.4); weight: 65.6 kg (6.6); height: 180.0 cm (5.0); fat mass: 6.72% (0.66); muscle mass: 33.3 kg (3.3); VO_2MAX: 66.5 ml · kg^-1·min^-1 (1.9)) completed this randomized crossover design clinical trial. Subjects underwent two interventions: they consumed placebo (<i>n</i> = 8) and glycerol (<i>n</i> = 8) acutely, before a rectangular test where dehydration, RPE, metabolic, kinematic, and thermographic variables were analyzed before, during and after the test.</p><p><strong>Results: </strong>After the intervention, significant differences were found between groups in body mass in favor of the placebo (Placebo: -2.23 kg vs Glycerol: -2.48 kg; <i>p</i> = 0.033). For other variables, no significant differences were found.</p><p><strong>Conclusion: </strong>Therefore, pre-exercise glycerol supplementation was not able to improve any dehydration, metabolic, kinematic, or thermographic variables during a rectangular test at temperature mid in international race walkers. Possibly, a higher environmental temperature could have generated a higher metabolic and thermoregulatory stress, generating differences between groups like other previous scientific evidence.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2346563"},"PeriodicalIF":5.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11057399/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140851393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Paraxanthine provides greater improvement in cognitive function than caffeine after performing a 10-km run.","authors":"Choongsung Yoo, Dante Xing, Drew E Gonzalez, Victoria Jenkins, Kay Nottingham, Broderick Dickerson, Megan Leonard, Joungbo Ko, Megan H Lewis, Mark Faries, Wesley Kephart, Martin Purpura, Ralf Jäger, Shawn D Wells, Kylin Liao, Ryan Sowinski, Christopher J Rasmussen, Richard B Kreider","doi":"10.1080/15502783.2024.2352779","DOIUrl":"10.1080/15502783.2024.2352779","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Rationale: &lt;/strong&gt;Intense exercise promotes fatigue and can impair cognitive function, particularly toward the end of competition when decision-making is often critical for success. For this reason, athletes often ingest caffeinated energy drinks prior to or during exercise to help them maintain focus, reaction time, and cognitive function during competition. However, caffeine habituation and genetic sensitivity to caffeine (CA) limit efficacy. Paraxanthine (PX) is a metabolite of caffeine reported to possess nootropic properties. This study examined whether ingestion of PX with and without CA affects pre- or post-exercise cognitive function.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;12 trained runners were randomly assigned to consume in a double-blind, randomized, and crossover manner 400 mg of a placebo (PL); 200 mg of PL + 200 mg of CA; 200 mg of PL + 200 mg of PX (ENFINITY®, Ingenious Ingredients); or 200 mg PX + 200 mg of CA (PX+CA) with a 7-14-day washout between treatments. Participants donated fasting blood samples and completed pre-supplementation (PRE) side effects questionnaires, the Berg-Wisconsin Card Sorting Test (BCST), and the Psychomotor Vigilance Task Test (PVTT). Participants then ingested the assigned treatment and rested for 60 minutes, repeated tests (PRE-EX), performed a 10-km run on a treadmill at a competition pace, and then repeated tests (POST-EX). Data were analyzed using General Linear Model (GLM) univariate analyses with repeated measures and percent changes from baseline with 95% confidence intervals.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;BCST correct responses in the PX treatment increased from PRE-EX to POST-EX (6.8% [1.5, 12.1], &lt;i&gt;p&lt;/i&gt; = 0.012). The error rate in the PL (23.5 [-2.8, 49.8] %, &lt;i&gt;p&lt;/i&gt; = 0.078) and CA treatment (31.5 [5.2, 57.8] %, &lt;i&gt;p&lt;/i&gt; = 0.02) increased from PRE-EX values with POST-EX errors tending to be lower with PX treatment compared to CA (-35.7 [-72.9, 1.4] %, &lt;i&gt;p&lt;/i&gt; = 0.059). POST-EX perseverative errors with PAR rules were significantly lower with PX treatment than with CA (-26.9 [-50.5, -3.4] %, &lt;i&gt;p&lt;/i&gt; = 0.026). Vigilance analysis revealed a significant interaction effect in Trial #2 mean reaction time values (&lt;i&gt;p&lt;/i&gt; = 0.049, &lt;math&gt;&lt;msubsup&gt;&lt;mi&gt;η&lt;/mi&gt;&lt;mi&gt;p&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msubsup&gt;&lt;/math&gt; &lt;sup&gt;=&lt;/sup&gt; 0.134, moderate to large effect) with POST-EX reaction times tending to be faster with PX and CA treatment. POST-EX mean reaction time of all trials with PX treatment was significantly faster than PL (-23.2 [-43.4, -2.4] %, &lt;i&gt;p&lt;/i&gt; = 0.029) and PX+CA (-29.6 [-50.3, -8.80] %, &lt;i&gt;p&lt;/i&gt; = 0.006) treatments. There was no evidence that PX ingestion adversely affected ratings of side effects associated with stimulant intake or clinical blood markers.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;Results provide some evidence that pre-exercise PX ingestion improves prefrontal cortex function, attenuates attentional decline, mitigates cognitive fatigue, and improves reaction time and vigilance. Addi","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2352779"},"PeriodicalIF":5.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11089923/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140898791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differences in perceived energy and macronutrient requirements across divisions in NCAA athletes.","authors":"K Michelle Singleton, Andrew R Jagim, Jamie McAllister-Deitrick, Marcos Daou, Chad M Kerksick","doi":"10.1080/15502783.2024.2365307","DOIUrl":"10.1080/15502783.2024.2365307","url":null,"abstract":"<p><strong>Background: </strong>Sports nutrition is an impactful component to sports performance. The purpose of the current study was to investigate the sports nutrition knowledge of National Collegiate Athletic Association collegiate athletes and assess self-reported perceived requirements for energy and macronutrient intake. A secondary aim was to evaluate the awareness of physical and emotional perceptions associated with mindful eating.</p><p><strong>Methods: </strong>Participants included NCAA Division I (DI, <i>n</i> = 45), II (DII, <i>n</i> = 31), and III (DIII, <i>n</i> = 47) athletes. Athletes completed a validated questionnaire designed to assess sports nutrition knowledge and were asked questions about their perceived dietary energy and macronutrient requirements. Daily energy intake values were calculated using a recommended relative energy intake value of 40, 50, and 60 kcal/kg/day for low, moderate, and high activity levels, respectively. Carbohydrate recommendations were calculated using 4, 6, and 8 g/kg/day, protein recommendations were calculated using relative intakes of 1.4, 1.6, and 1.8 g/kg/day, and fat recommendations were calculated from a relative percentage of total predicted daily energy requirements, equating to 15, 25, and 30% of daily energy. Additionally, athletes completed a questionnaire to assess mindfulness regarding eating habits.</p><p><strong>Results: </strong>Overall, athletes answered 45.5 ± 13.5% of questions correctly on the nutrition questionnaire with significant differences observed between male (48.6 ± 13.6%) and female athletes (43.6 ± 13.2%; <i>p</i> = 0.044), as well as significant differences observed between DI athlete scores (38.8 ± 14.1%) and DII athletes (47.7 ± 11.4%; <i>p</i> = 0.002), and DI athletes and DIII athletes (51.71 ± 11.83%; <i>p</i> =  <0.001). All athletes significantly (<i>p</i> < 0.001) underestimated daily energy intake requirements (female, 2,112 ± 575 kcal/day; male, 3,283 ± 538 kcal/day). The mindfulness eating habits total score was significantly higher in male athletes (65.1 ± 6.5) compared to female athletes (60.9 ± 9.5; <i>p</i> = 0.009).</p><p><strong>Conclusions: </strong>Division I, II, and III collegiate athletes have poor sports nutrition knowledge, with Division I athletes having exhibited lower scores compared to Division II and III athletes on the sports nutrition knowledge questionnaire. Athletes from all levels of collegiate sports underestimated their energy and macronutrient requirements. Differences in mindful eating habits among female and male athletes were also evident.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2365307"},"PeriodicalIF":5.1,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11168329/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141300895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inflated effect estimates for vitamin D supplementation are driven by common meta-analytical errors.","authors":"Eric T Trexler","doi":"10.1080/15502783.2024.2413668","DOIUrl":"10.1080/15502783.2024.2413668","url":null,"abstract":"<p><strong>Purpose: </strong>Han et al. (J Int Soc Sports Nutr 16:55, 2019) sought to quantify the effects of vitamin D supplementation on strength outcomes among athletes in a meta-analysis. The authors reported a pooled effect size (standardized mean difference; SMD) of -0.75 (95% CI: -1.82 to 0.32, p = 0.17) in favor of supplementation, but the analytical approach was not appropriate for a pooled analysis of randomized controlled trials and the effect sizes were calculated incorrectly. This letter discusses how these issues impact the results and interpretation of the paper, then provides an update on the estimated average effect of vitamin D on strength outcomes in athletes.</p><p><strong>Methods: </strong>Identified errors included the use of within-group rather than between-group effect size metrics, the use of standard error values in place of standard deviations, and failure to account for correlated observations within the model. The data were reanalyzed after correcting for these common meta-analytic errors.</p><p><strong>Results: </strong>The results of this reanalysis reflect a dramatically smaller and statistically nonsignificant pooled effect estimate of SMD = 0.16 (-0.24 to 0.56, p = 0.43) in favor of supplementation. Further, the model from this reanalysis has more favorable statistical characteristics than the original analysis, as evidenced by a fairly symmetrical funnel plot and a nonsignificant result for Cochrane's Q test (Q = 5.02, p = 0.41).</p><p><strong>Conclusion: </strong>In order to disseminate robust information to sports nutrition practitioners and researchers, it is critically important for meta-analyses to produce valid effect estimates that are appropriate for the underlying study designs and calculated without error. This letter highlights common errors to inform the calculation and interpretation of future meta-analyses in sports nutrition.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2413668"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11459837/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142381122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of Urolithin A effects on muscle endurance, strength, inflammation, oxidative stress, and protein metabolism in male athletes with resistance training: an 8-week randomized, double-blind, placebo-controlled study.","authors":"Haotian Zhao, Hongkang Zhu, Hezhang Yun, Jingqi Liu, Ge Song, Jin Teng, Dixin Zou, Naiyan Lu, Chang Liu","doi":"10.1080/15502783.2024.2419388","DOIUrl":"10.1080/15502783.2024.2419388","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;This study aimed to investigate the impact of Urolithin A (UA) on muscle endurance, muscle strength, inflammatory levels, oxidative stress, and protein metabolism status in resistance-trained male athletes.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Method: &lt;/strong&gt;An 8-week randomized, double-blind, placebo-controlled study was conducted with twenty resistance-trained male athletes. Participants were supplemented with 1 g of UA daily. Muscle strength and muscle endurance measures were assessed, and fasting venous blood samples and morning urine samples were collected to evaluate their oxidative stress levels, inflammatory markers, and protein metabolism status.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;There were no significant differences observed in terms of dietary energy intake and composition between the two assessments conducted within a 24-hour period. After 8 weeks of UA supplementation, compared to baseline measurements, the UA group exhibited increases in 1RM bench press and squat, although these changes were not statistically significant (Δ = 3.00 ± 0.17 kg, &lt;i&gt;p&lt;/i&gt; = 0.051, Δ = 1.35 ± 2.73 kg, &lt;i&gt;p&lt;/i&gt; = 0.499). However, significant improvements were noted in Maximum Voluntary Isometric Contraction (MVIC) and repetitions to failure (RTF) performance (Δ = 36.10 ± 0.62 NM, &lt;i&gt;p&lt;/i&gt; = 0.000; Δ = 2.00 ± 0.56, &lt;i&gt;p&lt;/i&gt; = 0.001). When compared to the placebo group, the UA supplementation for 8 weeks led to an increase in 1RM bench press and squat, although statistical significance was not reached (Δ = 3.50 ± 0.79 kg, &lt;i&gt;p&lt;/i&gt; = 0.462; Δ = 2.55 ± 1.36 kg, &lt;i&gt;p&lt;/i&gt; = 0.710). Furthermore, the group receiving UA supplementation, compared to the placebo group, showed significant improvements in MVIC and RTF (Δ = 43.50 ± 0.77 NM, &lt;i&gt;p&lt;/i&gt; = 0.048; Δ = 2.00 ± 1.22, &lt;i&gt;p&lt;/i&gt; = 0.011), indicating that the UA group exhibited superior performance enhancements in these metrics compared to the placebo group. After 8 weeks of UA supplementation, the UA group showed a significant decrease in 3-methylhistidine (3-MH) compared to baseline measurement (Δ=-2.38 ± 1.96 μmol/L, &lt;i&gt;p&lt;/i&gt; = 0.049). Additionally, the UA group exhibited a significant increase in C-reactive protein (CRP) compared to baseline (Δ = 0.71 ± 0.21 mg/L, &lt;i&gt;p&lt;/i&gt; = 0.001). However, there was no significant changes observed in Interleukin-6 (IL-6) (Δ=-1.00 ± 1.01 pg/mL, &lt;i&gt;p&lt;/i&gt; = 0.076), or superoxide dismutase (SOD) (Δ=-0.004 ± 0.72 U/mL, &lt;i&gt;p&lt;/i&gt; = 0.996) compared to baseline in the UA group. When compared to the placebo group, there was no significant difference observed in 3-MH in the UA group (Δ=-3.20 ± 0.31 μmol/L, &lt;i&gt;p&lt;/i&gt; = 0.36). In terms of inflammation markers, the UA group exhibited a significant decrease in CRP (Δ=-0.79 ± 0.38 mg/L, &lt;i&gt;p&lt;/i&gt; = 0.032) compared to the placebo group, whereas there was a decrease in IL-6 without statistical significance (Δ=-1.75 ± 0.45 pg/mL, &lt;i&gt;p&lt;/i&gt; = 0.215). Furthermore, the UA group showed a significant decrease in SOD compared to the placebo grou","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2419388"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11536656/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142564314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of a brand-specific, hemp-derived cannabidiol product on physiological, biochemical, and psychometric outcomes in healthy adults: a double-blind, randomized clinical trial.","authors":"Gianna F Mastrofini, Bridget A McFadden, Alexa J Chandler, Blaine S Lints, Harry P Cintineo, Nathaniel D Rhoades, Caroline S Vincenty, Sten O Stray-Gundersen, Abbi D Lane, Shawn M Arent","doi":"10.1080/15502783.2024.2370430","DOIUrl":"10.1080/15502783.2024.2370430","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Cannabidiol (CBD) is a non-psychoactive phyto-cannabinoid derived from the &lt;i&gt;Cannabis sativa&lt;/i&gt; plant. CBD exhibits various interactions at receptor sites, prompting the research of its potential anti-inflammatory, immunomodulatory, psychological, and pain-relieving effects. This study aimed to investigate the physiological, biochemical, and psychometric effects of a brand-specific, hemp-derived CBD product in healthy adults over a 12-week observation period.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;54 healthy males and females (age = 25 ± 7y; BMI = 24.82 ± 3.25 kg/m&lt;sup&gt;2&lt;/sup&gt;) recruited from a large Southeastern University completed the study. Participants arrived at the laboratory after &gt; 8 h of fasting, and &gt; 48 h without alcohol consumption and vigorous exercise. Following baseline measurements (height, weight, blood pressure, electrocardiogram (ECG), and blood work), participants were stratified by sex and randomized to either CBD or placebo groups. Products were administered double-blinded, with both given in liquid form containing medium-chain triglyceride oil, while the CBD product specifically contained 50 mg/mL of CBD. Participants were instructed to consume 1 mL of their product twice daily and were given enough product to last until their next laboratory visit. Data were collected at baseline and on days 30 ± 3, 60 ± 3, and 90 ± 3. Blood was drawn for analysis of immune and inflammatory biomarkers. Chronic pain among participants was calculated using urine samples according to the foundational pain index (FPI). Self-reported psychometric questionnaires were utilized (Cohen's Perceived Stress Scale, Pittsburgh Sleep Quality Index, Profile of Mood States,10-item Likert scale for perceived pain) to assess stress, sleep quality, mood state, and body discomfort. To determine overall wellbeing, participants completed a daily survey indicating if they missed work or school due to illness. Change from baseline was calculated for each measure, and mixed effects models were used to determine differences between groups over time while adjusting for baseline values (α = 0.05). Data are presented as mean ± standard deviation.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;There were no Group-by-Time interactions or Group or Time main effects for immune or inflammatory biomarkers (&lt;i&gt;p&lt;/i&gt; &gt; 0.05). Analyses revealed no Group-by-Time interactions or main effects observed for perceived stress, sleep quality, overall mood disturbance, and all the profile of mood state subscales (&lt;i&gt;p&lt;/i&gt; &gt; 0.05), except \"vigor-activity.\" A Time main effect was found for the sub-score for \"vigor-activity\" (&lt;i&gt;p&lt;/i&gt; = 0.007; Pre CBD = 19.5 ± 5.2, Post CBD = 17.3 ± 5.3; Pre PL = 19.0 ± 5.7, Post PL = 17.9 ± 7.1), which decreased from Visit 3 to Visit 4 (&lt;i&gt;p&lt;/i&gt; = 0.025) and from Visit 3 to Visit 5 (&lt;i&gt;p&lt;/i&gt; = 0.014). There was a Group main effect for FPI (&lt;i&gt;p&lt;/i&gt; = 0.028; Pre CBD = 11.9 ± 14.4, Post CBD = 8.8 ± 10.9; Pre PL = 9.0 ± 14.2, Post PL = 12.9 ± 11","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2370430"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11195455/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141432241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"International society of sports nutrition position stand: ketogenic diets.","authors":"Alex Leaf, Jeffrey A Rothschild, Tim M Sharpe, Stacy T Sims, Chad J Macias, Geoff G Futch, Michael D Roberts, Jeffrey R Stout, Michael J Ormsbee, Alan A Aragon, Bill I Campbell, Shawn M Arent, Dominic P D'Agostino, Michelle T Barrack, Chad M Kerksick, Richard B Kreider, Douglas S Kalman, Jose Antonio","doi":"10.1080/15502783.2024.2368167","DOIUrl":"10.1080/15502783.2024.2368167","url":null,"abstract":"<p><strong>Position statement: </strong>The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the use of a ketogenic diet in healthy exercising adults, with a focus on exercise performance and body composition. However, this review does not address the use of exogenous ketone supplements. The following points summarize the position of the ISSN.</p><p><p>1. A ketogenic diet induces a state of nutritional ketosis, which is generally defined as serum ketone levels above 0.5 mM. While many factors can impact what amount of daily carbohydrate intake will result in these levels, a broad guideline is a daily dietary carbohydrate intake of less than 50 grams per day.</p><p><p>2. Nutritional ketosis achieved through carbohydrate restriction and a high dietary fat intake is not intrinsically harmful and should not be confused with ketoacidosis, a life-threatening condition most commonly seen in clinical populations and metabolic dysregulation.</p><p><p>3. A ketogenic diet has largely neutral or detrimental effects on athletic performance compared to a diet higher in carbohydrates and lower in fat, despite achieving significantly elevated levels of fat oxidation during exercise (~1.5 g/min).</p><p><p>4. The endurance effects of a ketogenic diet may be influenced by both training status and duration of the dietary intervention, but further research is necessary to elucidate these possibilities. All studies involving elite athletes showed a performance decrement from a ketogenic diet, all lasting six weeks or less. Of the two studies lasting more than six weeks, only one reported a statistically significant benefit of a ketogenic diet.</p><p><p>5. A ketogenic diet tends to have similar effects on maximal strength or strength gains from a resistance training program compared to a diet higher in carbohydrates. However, a minority of studies show superior effects of non-ketogenic comparators.</p><p><p>6. When compared to a diet higher in carbohydrates and lower in fat, a ketogenic diet may cause greater losses in body weight, fat mass, and fat-free mass, but may also heighten losses of lean tissue. However, this is likely due to differences in calorie and protein intake, as well as shifts in fluid balance.</p><p><p>7. There is insufficient evidence to determine if a ketogenic diet affects males and females differently. However, there is a strong mechanistic basis for sex differences to exist in response to a ketogenic diet.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"21 1","pages":"2368167"},"PeriodicalIF":4.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11212571/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141457670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}