Pub Date : 2023-12-01Epub Date: 2023-11-10DOI: 10.1080/15502783.2023.2280113
Erica N Peters, Helena Yardley, Amy Harrison, Graham M L Eglit, Jose Antonio, Cynthia Turcotte, Marcel O Bonn-Miller
Background: Cannabinoid-containing products are marketed to athletes as promoting recovery, in spite of a lack of data on their safety and effects. This randomized, double-blind, placebo-controlled, repeated-dose pilot study tested the safety, tolerability, and preliminary effects on recovery of a formulation containing cannabidiol (CBD; 35 mg), cannabigerol (CBG; 50 mg), beta caryophyllene (BCP; 25 mg), branched-chain amino acids (BCAAs; 3.8 g), and magnesium citrate (420 mg).
Methods: Exercise-trained individuals (N = 40) underwent an experimental induction of delayed onset muscle soreness (DOMS) and completed follow-up visits 24-, 48-, and 72-hours post-DOMS. Participants were randomized to active or placebo formulation, and consumed the formulation twice per day for 3.5 days.
Results: There was one adverse event (AE) in the active group (diarrhea) and two AEs in placebo (dry mouth; eye rash/swollen eye). There was 100% self-reported compliance with formulation consumption across the two groups. For the primary outcome of interest, the estimate of effect for ratings of average soreness/discomfort 72 hours post-DOMS between active and placebo groups was -1.33 (85% confidence interval = -2.55, -0.10), suggesting moderate evidence of a treatment difference. The estimate of effect for the outcome of ratings of interference of soreness, discomfort, or stiffness on daily activities at work or home 48 hours post-DOMS was -1.82 (95% confidence interval = -3.64, -0.01), indicating a treatment difference of potential clinical importance. There was no significant effect between active and placebo groups on objective measures of recovery, sleep quality, or mood disturbance.
Conclusions: The tested formulation reduced interference of DOMS on daily activities, demonstrating its improvement on a functional aspect of recovery.
{"title":"A randomized, double-blind, placebo-controlled, repeated-dose pilot study of the safety, tolerability, and preliminary effects of a cannabidiol (CBD)- and cannabigerol (CBG)-based beverage powder to support recovery from delayed onset muscle soreness (DOMS).","authors":"Erica N Peters, Helena Yardley, Amy Harrison, Graham M L Eglit, Jose Antonio, Cynthia Turcotte, Marcel O Bonn-Miller","doi":"10.1080/15502783.2023.2280113","DOIUrl":"10.1080/15502783.2023.2280113","url":null,"abstract":"<p><strong>Background: </strong>Cannabinoid-containing products are marketed to athletes as promoting recovery, in spite of a lack of data on their safety and effects. This randomized, double-blind, placebo-controlled, repeated-dose pilot study tested the safety, tolerability, and preliminary effects on recovery of a formulation containing cannabidiol (CBD; 35 mg), cannabigerol (CBG; 50 mg), beta caryophyllene (BCP; 25 mg), branched-chain amino acids (BCAAs; 3.8 g), and magnesium citrate (420 mg).</p><p><strong>Methods: </strong>Exercise-trained individuals (<i>N</i> = 40) underwent an experimental induction of delayed onset muscle soreness (DOMS) and completed follow-up visits 24-, 48-, and 72-hours post-DOMS. Participants were randomized to active or placebo formulation, and consumed the formulation twice per day for 3.5 days.</p><p><strong>Results: </strong>There was one adverse event (AE) in the active group (diarrhea) and two AEs in placebo (dry mouth; eye rash/swollen eye). There was 100% self-reported compliance with formulation consumption across the two groups. For the primary outcome of interest, the estimate of effect for ratings of average soreness/discomfort 72 hours post-DOMS between active and placebo groups was -1.33 (85% confidence interval = -2.55, -0.10), suggesting moderate evidence of a treatment difference. The estimate of effect for the outcome of ratings of interference of soreness, discomfort, or stiffness on daily activities at work or home 48 hours post-DOMS was -1.82 (95% confidence interval = -3.64, -0.01), indicating a treatment difference of potential clinical importance. There was no significant effect between active and placebo groups on objective measures of recovery, sleep quality, or mood disturbance.</p><p><strong>Conclusions: </strong>The tested formulation reduced interference of DOMS on daily activities, demonstrating its improvement on a functional aspect of recovery.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2280113"},"PeriodicalIF":5.1,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10653658/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72014642","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}
Pub Date : 2023-12-01Epub Date: 2023-11-29DOI: 10.1080/15502783.2023.2286286
Nisha Charkoudian, Jason K W Lee, Gabrielle E W Giersch, Loretta DiPietro, Nina Stachenfeld
{"title":"Different perspectives on women's health, nutrition and endurance exercise.","authors":"Nisha Charkoudian, Jason K W Lee, Gabrielle E W Giersch, Loretta DiPietro, Nina Stachenfeld","doi":"10.1080/15502783.2023.2286286","DOIUrl":"10.1080/15502783.2023.2286286","url":null,"abstract":"","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2286286"},"PeriodicalIF":5.1,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11018311/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138451767","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}
Pub Date : 2023-12-01Epub Date: 2023-10-04DOI: 10.1080/15502783.2023.2265888
Raquel Vaquero-Cristóbal, Ana Catarina-Moreira, Francisco Esparza-Ros, Carlos Barrigas, Mario Albaladejo-Saura, Filomena Vieira
<p><strong>Background: </strong>The skinfold caliper reading of the skinfold thickness depends on its dynamic compressibility. This has led to the fact that, while it is indicated that skinfold readings should be taken when the reading is stable, there is no consensus on at what second the reading should be taken after the application of the skinfold caliper. The new Lipowise PRO digital skinfold caliper was used to analyze the evolution of skinfold readings under skinfold caliper pressure. The aim of the present investigation were: a) to analyze the evolution of the reading time of individual skinfolds when subjected to skinfold caliper pressure and when the skinfold reading reaches stability; b) to describe the physical behavior of skinfold tissues' time response to skinfold caliper pressure, and to explore differences between sites and subjects' skinfolds compressibility; and c) to analyze the sex differences in both the reading and the evolution of the skinfold over time.</p><p><strong>Methods: </strong>A descriptive cross-sectional design was followed with a convenience sample of 165 healthy young adults (79 males and 86 females), with eight skinfolds measured using the Lipowise PRO skinfold caliper. The Lipowise PRO skinfold caliper uses a programmable reading time allowing for the measurement of the skinfold's thickness at a rate of 100 times per second, and monitoring skinfold behavior over the 3-second measurement period, thereby enabling the assessment of the tissue response to the constant force exerted by the skinfold caliper jaws.</p><p><strong>Results: </strong>All skinfolds showed statistical differences in terms of compressibility characteristics (<i>p</i> < 0.001). Significant differences were found between measurement time points for individual skinfolds and sum of skinfolds (<i>p</i> < 0.001-0.025). Stabilization being found depending on the skinfold measured from 1.5 seconds for biceps, subscapular, iliac crest, supraspinale, abdominal, and thigh skinfolds; 2.0 seconds for ∑6 and ∑8 skinfolds; and 2.5 seconds for triceps and calf skinfolds. It was observed an effect of sex on this issue (<i>p</i> < 0.001-0.030). More specifically, in the case of males, the supraspinale and abdominal skinfolds stabilized after 1.5 seconds; the calf skinfold and ∑6 and ∑8 skinfolds stabilized after 2 seconds; while the rest of the skinfolds did not stabilize until 3 seconds. In the case of females, no stabilization of the triceps skinfold was found, while the rest of the individual skinfolds and the ∑6 and ∑8 skinfolds stabilized from 1.5 seconds. A regression analysis indicated that skinfold thickness could be predicted based on measurement time in 50-77% of the cases (<i>p</i> = 0.001).</p><p><strong>Conclusion: </strong>A skinfold caliper application, using the digital caliper Lipowise PRO, of three seconds may be sufficient for achieving stability in the measurement and for obtaining the minimum value for most individual and sum of skinfolds
背景:皮褶厚度的皮褶卡尺读数取决于其动态压缩性。这导致了这样一个事实,即虽然有人指出,应在读数稳定时读取皮褶读数,但对于应用皮褶卡尺后应在哪一秒读取读数,目前还没有达成共识。新的Lipowise PRO数字皮褶卡尺用于分析皮褶卡尺压力下皮褶读数的演变。本研究的目的是:a)分析当受到皮褶卡尺压力时以及当皮褶读数达到稳定时,单个皮褶读数时间的演变;b) 描述皮褶组织对皮褶卡尺压力的时间响应的物理行为,并探讨部位和受试者皮褶压缩性之间的差异;以及c)分析皮褶在阅读和进化过程中的性别差异。方法:采用描述性横断面设计,以165名健康年轻人(79名男性和86名女性)为方便样本,使用Lipowise PRO皮褶卡尺测量8个皮褶。Lipowise PRO皮褶钳使用可编程读取时间,允许以每秒100次的速度测量皮褶厚度,并在3秒的测量期内监测皮褶行为,从而能够评估组织对皮褶钳钳口施加的恒定力的反应。结果:所有皮褶在压缩特性方面均存在统计学差异(p p p p = 0.001)。结论:使用Lipowise PRO数字卡尺应用皮褶卡尺3秒可能足以实现测量的稳定性,并获得大多数个体和皮褶总和的最小值。然而,在某些人身上进行某些皮褶手术时,可能需要更多的时间,这因性别而异。
{"title":"Skinfolds compressibility and digital caliper's time response in skinfold measurement in male and female young adults.","authors":"Raquel Vaquero-Cristóbal, Ana Catarina-Moreira, Francisco Esparza-Ros, Carlos Barrigas, Mario Albaladejo-Saura, Filomena Vieira","doi":"10.1080/15502783.2023.2265888","DOIUrl":"10.1080/15502783.2023.2265888","url":null,"abstract":"<p><strong>Background: </strong>The skinfold caliper reading of the skinfold thickness depends on its dynamic compressibility. This has led to the fact that, while it is indicated that skinfold readings should be taken when the reading is stable, there is no consensus on at what second the reading should be taken after the application of the skinfold caliper. The new Lipowise PRO digital skinfold caliper was used to analyze the evolution of skinfold readings under skinfold caliper pressure. The aim of the present investigation were: a) to analyze the evolution of the reading time of individual skinfolds when subjected to skinfold caliper pressure and when the skinfold reading reaches stability; b) to describe the physical behavior of skinfold tissues' time response to skinfold caliper pressure, and to explore differences between sites and subjects' skinfolds compressibility; and c) to analyze the sex differences in both the reading and the evolution of the skinfold over time.</p><p><strong>Methods: </strong>A descriptive cross-sectional design was followed with a convenience sample of 165 healthy young adults (79 males and 86 females), with eight skinfolds measured using the Lipowise PRO skinfold caliper. The Lipowise PRO skinfold caliper uses a programmable reading time allowing for the measurement of the skinfold's thickness at a rate of 100 times per second, and monitoring skinfold behavior over the 3-second measurement period, thereby enabling the assessment of the tissue response to the constant force exerted by the skinfold caliper jaws.</p><p><strong>Results: </strong>All skinfolds showed statistical differences in terms of compressibility characteristics (<i>p</i> < 0.001). Significant differences were found between measurement time points for individual skinfolds and sum of skinfolds (<i>p</i> < 0.001-0.025). Stabilization being found depending on the skinfold measured from 1.5 seconds for biceps, subscapular, iliac crest, supraspinale, abdominal, and thigh skinfolds; 2.0 seconds for ∑6 and ∑8 skinfolds; and 2.5 seconds for triceps and calf skinfolds. It was observed an effect of sex on this issue (<i>p</i> < 0.001-0.030). More specifically, in the case of males, the supraspinale and abdominal skinfolds stabilized after 1.5 seconds; the calf skinfold and ∑6 and ∑8 skinfolds stabilized after 2 seconds; while the rest of the skinfolds did not stabilize until 3 seconds. In the case of females, no stabilization of the triceps skinfold was found, while the rest of the individual skinfolds and the ∑6 and ∑8 skinfolds stabilized from 1.5 seconds. A regression analysis indicated that skinfold thickness could be predicted based on measurement time in 50-77% of the cases (<i>p</i> = 0.001).</p><p><strong>Conclusion: </strong>A skinfold caliper application, using the digital caliper Lipowise PRO, of three seconds may be sufficient for achieving stability in the measurement and for obtaining the minimum value for most individual and sum of skinfolds","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2265888"},"PeriodicalIF":5.1,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10557569/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41134198","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}
<p><strong>Background: </strong>Based on stoichiometric assumptions, and real-time assessment of expired carbon dioxide (%CO<sub>2</sub>) and flow rate, the Lumen device provides potential for consumers/athletes to monitor metabolic responses to dietary programs outside of laboratory conditions. However, there is a paucity of research exploring device efficacy. This study aimed to evaluate Lumen device response to: i) a high-carbohydrate meal under laboratory conditions, and ii) a short-term low- or high-carbohydrate diet in healthy volunteers.</p><p><strong>Methods: </strong>Following institutional ethical approval, 12 healthy volunteers (age: 36 ± 4 yrs; body mass: 72.1 ± 3.6 kg; height: 1.71 ± 0.02 m) performed Lumen breath and Douglas bag expired air measures under fasted laboratory conditions and at 30 and 60 min after a high-carbohydrate (2 g·kg<sup>-1</sup>) meal, along with capilliarized blood glucose assessment. Data were analyzed using a one-way ANOVA, with ordinary least squares regression used to assess the model between Lumen expired carbon dioxide percentage (L%CO<sub>2</sub>) and respiratory exchange ratio (RER). In a separate phase, 27 recreationally active adults (age: 42 ± 2 yrs; body mass: 71.9 ± 1.9 kg; height: 1.72 ± 0.02 m) completed a 7-day low- (~20% of energy intake [EI]; LOW) or high-carbohydrate diet (~60% of EI; HIGH) in a randomized, cross-over design under free-living conditions. L%CO<sub>2</sub> and derived Lumen Index (L<sub>I</sub>) were recorded daily across morning (fasted and post-breakfast) and evening (pre/post meal, pre-bed) periods. Repeated measures ANOVA were employed for main analyses, with Bonferroni post-hoc assessment applied (<i>P</i> ≤ 0.05).</p><p><strong>Results: </strong>Following the carbohydrate test-meal, L%CO<sub>2</sub> increased from 4.49 ± 0.05% to 4.80 ± 0.06% by 30 min, remaining elevated at 4.76 ± 0.06% by 60 min post-feeding (<i>P</i> < 0.001, η<sub>p</sub><sup>2</sup> = 0.74). Similarly, RER increased by 18.1% from 0.77 ± 0.03 to 0.91 ± 0.02 by 30 min post-meal (<i>P</i> = 0.002). When considering peak data, regression analysis demonstrated a significant model effect between RER and L%CO<sub>2</sub> (F = 5.62, <i>P</i> = 0.03, R<sup>2</sup> = 0.20). Following main dietary interventions, no significant interactions (diet × day) were found. However, main diet effects were evident across all time-points assessed, highlighting significant differences for both L%CO<sub>2</sub> and L<sub>I</sub> between LOW and HIGH conditions (<i>P</i> < 0.003). For L%CO<sub>2</sub>, this was particularly noted under fasted (4.35 ± 0.07 vs. 4.46 ± 0.06%, <i>P</i> = 0.001), pre-evening meal (4.35 ± 0.07 vs. 4.50 ± 0.06%, <i>P</i> < 0.001), and pre-bed time-points (4.51 ± 0.08 vs. 4.61 ± 0.06%, <i>P</i> = 0.005).</p><p><strong>Conclusion: </strong>Our findings demonstrated that a portable, home-use metabolic device (Lumen) detected significantly increased expired %CO<sub>2</sub> in response to a high-carbohy
{"title":"The efficacy of a home-use metabolic device (Lumen) in response to a short-term low and high carbohydrate diet in healthy volunteers.","authors":"Justin Roberts, Dirk Dugdale-Duwell, Joseph Lillis, Jorge Marques Pinto, Ash Willmott, Shlomo Yeshurun, Merav Mor, Tjeu Souren","doi":"10.1080/15502783.2023.2185537","DOIUrl":"10.1080/15502783.2023.2185537","url":null,"abstract":"<p><strong>Background: </strong>Based on stoichiometric assumptions, and real-time assessment of expired carbon dioxide (%CO<sub>2</sub>) and flow rate, the Lumen device provides potential for consumers/athletes to monitor metabolic responses to dietary programs outside of laboratory conditions. However, there is a paucity of research exploring device efficacy. This study aimed to evaluate Lumen device response to: i) a high-carbohydrate meal under laboratory conditions, and ii) a short-term low- or high-carbohydrate diet in healthy volunteers.</p><p><strong>Methods: </strong>Following institutional ethical approval, 12 healthy volunteers (age: 36 ± 4 yrs; body mass: 72.1 ± 3.6 kg; height: 1.71 ± 0.02 m) performed Lumen breath and Douglas bag expired air measures under fasted laboratory conditions and at 30 and 60 min after a high-carbohydrate (2 g·kg<sup>-1</sup>) meal, along with capilliarized blood glucose assessment. Data were analyzed using a one-way ANOVA, with ordinary least squares regression used to assess the model between Lumen expired carbon dioxide percentage (L%CO<sub>2</sub>) and respiratory exchange ratio (RER). In a separate phase, 27 recreationally active adults (age: 42 ± 2 yrs; body mass: 71.9 ± 1.9 kg; height: 1.72 ± 0.02 m) completed a 7-day low- (~20% of energy intake [EI]; LOW) or high-carbohydrate diet (~60% of EI; HIGH) in a randomized, cross-over design under free-living conditions. L%CO<sub>2</sub> and derived Lumen Index (L<sub>I</sub>) were recorded daily across morning (fasted and post-breakfast) and evening (pre/post meal, pre-bed) periods. Repeated measures ANOVA were employed for main analyses, with Bonferroni post-hoc assessment applied (<i>P</i> ≤ 0.05).</p><p><strong>Results: </strong>Following the carbohydrate test-meal, L%CO<sub>2</sub> increased from 4.49 ± 0.05% to 4.80 ± 0.06% by 30 min, remaining elevated at 4.76 ± 0.06% by 60 min post-feeding (<i>P</i> < 0.001, η<sub>p</sub><sup>2</sup> = 0.74). Similarly, RER increased by 18.1% from 0.77 ± 0.03 to 0.91 ± 0.02 by 30 min post-meal (<i>P</i> = 0.002). When considering peak data, regression analysis demonstrated a significant model effect between RER and L%CO<sub>2</sub> (F = 5.62, <i>P</i> = 0.03, R<sup>2</sup> = 0.20). Following main dietary interventions, no significant interactions (diet × day) were found. However, main diet effects were evident across all time-points assessed, highlighting significant differences for both L%CO<sub>2</sub> and L<sub>I</sub> between LOW and HIGH conditions (<i>P</i> < 0.003). For L%CO<sub>2</sub>, this was particularly noted under fasted (4.35 ± 0.07 vs. 4.46 ± 0.06%, <i>P</i> = 0.001), pre-evening meal (4.35 ± 0.07 vs. 4.50 ± 0.06%, <i>P</i> < 0.001), and pre-bed time-points (4.51 ± 0.08 vs. 4.61 ± 0.06%, <i>P</i> = 0.005).</p><p><strong>Conclusion: </strong>Our findings demonstrated that a portable, home-use metabolic device (Lumen) detected significantly increased expired %CO<sub>2</sub> in response to a high-carbohy","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2185537"},"PeriodicalIF":4.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9987730/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9111962","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}
Pub Date : 2023-12-01DOI: 10.1080/15502783.2023.2171314
Andrew R Jagim, Patrick S Harty, Grant M Tinsley, Chad M Kerksick, Adam M Gonzalez, Richard B Kreider, Shawn M Arent, Ralf Jager, Abbie E Smith-Ryan, Jeffrey R Stout, Bill I Campbell, Trisha VanDusseldorp, Jose Antonio
<p><p>Position Statement: The <i>International Society of Sports Nutrition</i> (ISSN) bases the following position stand on a critical analysis of the literature regarding the effects of energy drink (ED) or energy shot (ES) consumption on acute exercise performance, metabolism, and cognition, along with synergistic exercise-related performance outcomes and training adaptations. The following 13 points constitute the consensus of the Society and have been approved by the Research Committee of the Society: Energy drinks (ED) commonly contain caffeine, taurine, ginseng, guarana, carnitine, choline, B vitamins (vitamins B1, B2, B3, B5, B6, B9, and B12), vitamin C, vitamin A (beta carotene), vitamin D, electrolytes (sodium, potassium, magnesium, and calcium), sugars (nutritive and non-nutritive sweeteners), tyrosine, and L-theanine, with prevalence for each ingredient ranging from 1.3 to 100%. Energy drinks can enhance acute aerobic exercise performance, largely influenced by the amount of caffeine (> 200 mg or >3 mg∙kg bodyweight [BW<sup>-1</sup>]) in the beverage. Although ED and ES contain several nutrients that are purported to affect mental and/or physical performance, the primary ergogenic nutrients in most ED and ES based on scientific evidence appear to be caffeine and/or the carbohydrate provision. The ergogenic value of caffeine on mental and physical performance has been well-established, but the potential additive benefits of other nutrients contained in ED and ES remains to be determined. Consuming ED and ES 10-60 minutes before exercise can improve mental focus, alertness, anaerobic performance, and/or endurance performance with doses >3 mg∙kg BW<sup>-1</sup>. Consuming ED and ES containing at least 3 mg∙kg BW<sup>-1</sup> caffeine is most likely to benefit maximal lower-body power production. Consuming ED and ES can improve endurance, repeat sprint performance, and sport-specific tasks in the context of team sports. Many ED and ES contain numerous ingredients that either have not been studied or evaluated in combination with other nutrients contained in the ED or ES. For this reason, these products need to be studied to demonstrate efficacy of single- and multi-nutrient formulations for physical and cognitive performance as well as for safety. Limited evidence is available to suggest that consumption of low-calorie ED and ES during training and/or weight loss trials may provide ergogenic benefit and/or promote additional weight control, potentially through enhanced training capacity. However, ingestion of higher calorie ED may promote weight gain if the energy intake from consumption of ED is not carefully considered as part of the total daily energy intake. Individuals should consider the impact of regular coingestion of high glycemic index carbohydrates from ED and ES on metabolic health, blood glucose, and insulin levels. Adolescents (aged 12 through 18) should exercise caution and seek parental guidance when considering the consump
{"title":"International society of sports nutrition position stand: energy drinks and energy shots.","authors":"Andrew R Jagim, Patrick S Harty, Grant M Tinsley, Chad M Kerksick, Adam M Gonzalez, Richard B Kreider, Shawn M Arent, Ralf Jager, Abbie E Smith-Ryan, Jeffrey R Stout, Bill I Campbell, Trisha VanDusseldorp, Jose Antonio","doi":"10.1080/15502783.2023.2171314","DOIUrl":"10.1080/15502783.2023.2171314","url":null,"abstract":"<p><p>Position Statement: The <i>International Society of Sports Nutrition</i> (ISSN) bases the following position stand on a critical analysis of the literature regarding the effects of energy drink (ED) or energy shot (ES) consumption on acute exercise performance, metabolism, and cognition, along with synergistic exercise-related performance outcomes and training adaptations. The following 13 points constitute the consensus of the Society and have been approved by the Research Committee of the Society: Energy drinks (ED) commonly contain caffeine, taurine, ginseng, guarana, carnitine, choline, B vitamins (vitamins B1, B2, B3, B5, B6, B9, and B12), vitamin C, vitamin A (beta carotene), vitamin D, electrolytes (sodium, potassium, magnesium, and calcium), sugars (nutritive and non-nutritive sweeteners), tyrosine, and L-theanine, with prevalence for each ingredient ranging from 1.3 to 100%. Energy drinks can enhance acute aerobic exercise performance, largely influenced by the amount of caffeine (> 200 mg or >3 mg∙kg bodyweight [BW<sup>-1</sup>]) in the beverage. Although ED and ES contain several nutrients that are purported to affect mental and/or physical performance, the primary ergogenic nutrients in most ED and ES based on scientific evidence appear to be caffeine and/or the carbohydrate provision. The ergogenic value of caffeine on mental and physical performance has been well-established, but the potential additive benefits of other nutrients contained in ED and ES remains to be determined. Consuming ED and ES 10-60 minutes before exercise can improve mental focus, alertness, anaerobic performance, and/or endurance performance with doses >3 mg∙kg BW<sup>-1</sup>. Consuming ED and ES containing at least 3 mg∙kg BW<sup>-1</sup> caffeine is most likely to benefit maximal lower-body power production. Consuming ED and ES can improve endurance, repeat sprint performance, and sport-specific tasks in the context of team sports. Many ED and ES contain numerous ingredients that either have not been studied or evaluated in combination with other nutrients contained in the ED or ES. For this reason, these products need to be studied to demonstrate efficacy of single- and multi-nutrient formulations for physical and cognitive performance as well as for safety. Limited evidence is available to suggest that consumption of low-calorie ED and ES during training and/or weight loss trials may provide ergogenic benefit and/or promote additional weight control, potentially through enhanced training capacity. However, ingestion of higher calorie ED may promote weight gain if the energy intake from consumption of ED is not carefully considered as part of the total daily energy intake. Individuals should consider the impact of regular coingestion of high glycemic index carbohydrates from ED and ES on metabolic health, blood glucose, and insulin levels. Adolescents (aged 12 through 18) should exercise caution and seek parental guidance when considering the consump","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2171314"},"PeriodicalIF":4.5,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9987737/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10277411","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}
Pub Date : 2023-12-01Epub Date: 2023-11-16DOI: 10.1080/15502783.2023.2282051
Sepideh Pirmohammadi, Mohammad Hemmatinafar, Javad Nemati, Babak Imanian, Mohammad Hassan Abdollahi
<p><strong>Background: </strong>The consumption of fast absorption sources containing caffeine, such as caffeinated gum and coffee mouth rinsing, has been considered a practical nutritional strategy among athletes. Therefore, this study aimed to determine the effect of early absorption sources containing caffeine on the performance of female table tennis players.</p><p><strong>Method: </strong>Eighteen female table tennis players randomly participated in this randomized, double-blind, and crossover designed study. Before starting the test, the participants attended a familiarization session. In each test session, participants were randomly assigned to one of three conditions including chewing caffeinated gum (CG, <i>n</i> = 6), coffee mouth rinsing (CMR, <i>n</i> = 6) and placebo capsule (PLA, <i>n</i> = 6). All participants consumed caffeine with an average dose of ∼3 to 4.5 mg·kg<sup>-1</sup>. The one-week interval was considered a washout period for each condition. Each test session included measurement of functional, skill and cognitive tests. Skill tests included serve, forehand drive, backhand push and counter tests. The Cognitive function measured by color recognition test, and functional tests included agility, hand movement speed, the explosive power of the upper body and lower body, hand-eye coordination and hand grip strength tests. The collected data were analyzed (with SPSS Windows software) by repeated measure ANOVA analysis and Bonferroni post hoc test at <i>P</i> ≤ 0.05 level.</p><p><strong>Results: </strong>The findings of the present study illustrated that CG and CMR increased significantly agility and reduced the amounts of errors in the cognitive test compared to PLA (<i>p</i> < 0.05), While there was no significant difference between CG and CMR (<i>p</i> > 0.05). Also, CG and CMR compared to PLA and CMR compared to CG rose significantly hand movement speed and movement speed (<i>p</i> < 0.05), and CMR compared to PLA increased significantly hand-eye coordination, isometric hand strength, service accuracy and forehand drive (<i>p</i> < 0.05). However, CG compared to PLA and CMR had no significant effect on hand-eye coordination, isometric hand strength, service accuracy and forehand drive (<i>p</i> > 0.05). In addition, CG and CMR enhanced significantly the explosive power of the lower body compared to PLA (<i>p</i> < 0.05), While there was no significant difference between CG and CMR (<i>p</i> > 0.05). Also, CG and CMR compared to PLA and CG compared to CMR had no significant effect on the explosive power of the upper body, backhand, and counter skills (<i>p</i> > 0.05). Furthermore, CG increased significantly accuracy in the service test compared to PLA (<i>p</i> < 0.05).</p><p><strong>Conclusion: </strong>According to the results, it seems that early absorption sources of caffeine (CMR and CG) are efficient strategies for improving the specific performance of female table tennis players. However, allegedly CMR and CG have a
背景:食用含有咖啡因的快速吸收源,如含咖啡因口香糖和咖啡漱口水,被认为是运动员的一种实用的营养策略。因此,本研究旨在确定含咖啡因的早期吸收源对女乒乓球运动员表现的影响。方法:18名女子乒乓球运动员随机参与,采用随机、双盲、交叉设计。在开始测试之前,参与者参加了一个熟悉会议。在每次测试中,参与者被随机分配到三种情况中的一种,包括咀嚼含咖啡因的口香糖(CG, n = 6),咖啡漱口水(CMR, n = 6)和安慰剂胶囊(PLA, n = 6)。所有参与者均摄入平均剂量为~ 3至4.5 mg·kg-1的咖啡因。一周的间隔被认为是每个条件的洗脱期。每个测试阶段包括功能测试、技能测试和认知测试。技术测试包括发球、正手发球、反手推球和反击测试。认知功能测试包括灵敏性测试、手部运动速度测试、上半身和下半身爆发力测试、手眼协调测试和手握力测试。收集的资料采用SPSS Windows软件进行重复测量方差分析和Bonferroni事后检验,P≤0.05。结果:本研究结果表明,与PLA相比,CG和CMR显著提高了认知测试的敏捷性,减少了认知测试的错误率(p p > 0.05)。此外,CG和CMR与PLA相比,CMR与CG相比,手部运动速度和运动速度显著提高(p p p > 0.05)。此外,与PLA相比,CG和CMR显著增强了下体的爆发力(p p > 0.05)。此外,CG和CMR与PLA相比,CG和CMR与CMR相比,对上身爆发力、反手和反技术没有显著影响(p > 0.05)。结论:早期咖啡因吸收源(CMR和CG)是提高女子乒乓球运动员专项成绩的有效策略。然而,与技能测试相比,CMR和CG在功能和认知测试中有更好的效果。
{"title":"Early absorption sources of caffeine can be a useful strategy for improving female table tennis players-specific performance.","authors":"Sepideh Pirmohammadi, Mohammad Hemmatinafar, Javad Nemati, Babak Imanian, Mohammad Hassan Abdollahi","doi":"10.1080/15502783.2023.2282051","DOIUrl":"10.1080/15502783.2023.2282051","url":null,"abstract":"<p><strong>Background: </strong>The consumption of fast absorption sources containing caffeine, such as caffeinated gum and coffee mouth rinsing, has been considered a practical nutritional strategy among athletes. Therefore, this study aimed to determine the effect of early absorption sources containing caffeine on the performance of female table tennis players.</p><p><strong>Method: </strong>Eighteen female table tennis players randomly participated in this randomized, double-blind, and crossover designed study. Before starting the test, the participants attended a familiarization session. In each test session, participants were randomly assigned to one of three conditions including chewing caffeinated gum (CG, <i>n</i> = 6), coffee mouth rinsing (CMR, <i>n</i> = 6) and placebo capsule (PLA, <i>n</i> = 6). All participants consumed caffeine with an average dose of ∼3 to 4.5 mg·kg<sup>-1</sup>. The one-week interval was considered a washout period for each condition. Each test session included measurement of functional, skill and cognitive tests. Skill tests included serve, forehand drive, backhand push and counter tests. The Cognitive function measured by color recognition test, and functional tests included agility, hand movement speed, the explosive power of the upper body and lower body, hand-eye coordination and hand grip strength tests. The collected data were analyzed (with SPSS Windows software) by repeated measure ANOVA analysis and Bonferroni post hoc test at <i>P</i> ≤ 0.05 level.</p><p><strong>Results: </strong>The findings of the present study illustrated that CG and CMR increased significantly agility and reduced the amounts of errors in the cognitive test compared to PLA (<i>p</i> < 0.05), While there was no significant difference between CG and CMR (<i>p</i> > 0.05). Also, CG and CMR compared to PLA and CMR compared to CG rose significantly hand movement speed and movement speed (<i>p</i> < 0.05), and CMR compared to PLA increased significantly hand-eye coordination, isometric hand strength, service accuracy and forehand drive (<i>p</i> < 0.05). However, CG compared to PLA and CMR had no significant effect on hand-eye coordination, isometric hand strength, service accuracy and forehand drive (<i>p</i> > 0.05). In addition, CG and CMR enhanced significantly the explosive power of the lower body compared to PLA (<i>p</i> < 0.05), While there was no significant difference between CG and CMR (<i>p</i> > 0.05). Also, CG and CMR compared to PLA and CG compared to CMR had no significant effect on the explosive power of the upper body, backhand, and counter skills (<i>p</i> > 0.05). Furthermore, CG increased significantly accuracy in the service test compared to PLA (<i>p</i> < 0.05).</p><p><strong>Conclusion: </strong>According to the results, it seems that early absorption sources of caffeine (CMR and CG) are efficient strategies for improving the specific performance of female table tennis players. However, allegedly CMR and CG have a","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2282051"},"PeriodicalIF":5.1,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11018319/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136397971","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}
Pub Date : 2023-08-01DOI: 10.1080/15502783.2023.2235311
Chad M Kerksick, Trisha VanDusseldorp, Douglas Kalman, Jose Antonio
Background: Previous research demonstrates body composition comparisons relative to their dominant arm vs non-dominant arm in collegiate baseball players. Further research demonstrates body composition comparisons relative to their position in collegiate baseball players. Though there is a vast amount of literature on nonprofessional baseball players, there is little research that analyzes body composition in professional baseball players. Therefore, the purpose of this study is to compare body composition variables by position in professional baseball players. We hypothesize that differences will exist in body mass and composition between positions. Methods: 178 (n = 60 Infield, n = 23 Outfield, n = 95 Pitcher) professional baseball players (22.3 ± 3.1 yrs.; 184.8 ± 6.7 cm) were used for the current study. The assessment was collected in a noninvasive bioelectric impedance analyzer machine (InBody770), in which the athlete stepped on the scale in the morning, before eating for at least 2 hours prior to the assessment and was well hydrated. Hydration levels were measured through an osmolality meter (Atago PAL-mOsm) with a score of no higher than 600 mOsmol/ kgH2O. One-Way ANOVA was utilized to analyze the main effects of the group. The Bonferroni Post Hoc analysis was utilized to compare positions, and significance was set at P ≤ 0.05. Results: There is a significant main effect of the group for body fat percentage (BF) (P = .007), body weight (BW) (P < .001), fat-free mass (FFM) (P < .001), and fat mass (FM)
{"title":"Proceedings of the Twentieth International Society of Sports Nutrition (ISSN) Conference and Expo.","authors":"Chad M Kerksick, Trisha VanDusseldorp, Douglas Kalman, Jose Antonio","doi":"10.1080/15502783.2023.2235311","DOIUrl":"https://doi.org/10.1080/15502783.2023.2235311","url":null,"abstract":"Background: Previous research demonstrates body composition comparisons relative to their dominant arm vs non-dominant arm in collegiate baseball players. Further research demonstrates body composition comparisons relative to their position in collegiate baseball players. Though there is a vast amount of literature on nonprofessional baseball players, there is little research that analyzes body composition in professional baseball players. Therefore, the purpose of this study is to compare body composition variables by position in professional baseball players. We hypothesize that differences will exist in body mass and composition between positions. Methods: 178 (n = 60 Infield, n = 23 Outfield, n = 95 Pitcher) professional baseball players (22.3 ± 3.1 yrs.; 184.8 ± 6.7 cm) were used for the current study. The assessment was collected in a noninvasive bioelectric impedance analyzer machine (InBody770), in which the athlete stepped on the scale in the morning, before eating for at least 2 hours prior to the assessment and was well hydrated. Hydration levels were measured through an osmolality meter (Atago PAL-mOsm) with a score of no higher than 600 mOsmol/ kgH2O. One-Way ANOVA was utilized to analyze the main effects of the group. The Bonferroni Post Hoc analysis was utilized to compare positions, and significance was set at P ≤ 0.05. Results: There is a significant main effect of the group for body fat percentage (BF) (P = .007), body weight (BW) (P < .001), fat-free mass (FFM) (P < .001), and fat mass (FM)","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 sup2","pages":"2235311"},"PeriodicalIF":5.1,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10388812/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9909802","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}
Pub Date : 2023-04-01DOI: 10.1080/15502783.2023.2187955
Trisha VanDusseldorp, Chad M Kerksick, Erik Bustillo, Douglas Kalman, Jose Antonio
{"title":"Proceedings of the Nineteenth International Society of Sports Nutrition (ISSN) Conference and Expo.","authors":"Trisha VanDusseldorp, Chad M Kerksick, Erik Bustillo, Douglas Kalman, Jose Antonio","doi":"10.1080/15502783.2023.2187955","DOIUrl":"https://doi.org/10.1080/15502783.2023.2187955","url":null,"abstract":"","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 sup1","pages":"2187955"},"PeriodicalIF":5.1,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10078124/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9347816","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}
Pub Date : 2023-01-01DOI: 10.1080/15502783.2023.2166366
Pedro L Valenzuela, Lidia B Alejo, Almudena Montalvo-Pérez, Diego Ojanguren, Miguel Górriz, Itziar Pagola, Laureano M Ozcoidi, Alejandro Lucia, David Barranco-Gil
Background: The effects of pre-sleep protein supplementation on endurance athletes remain unclear, particularly whether its potential benefits are due to the timing of protein intake or solely to an increased total protein intake. We assessed the effects of pre-sleep protein supplementation in professional cyclists during a training camp accounting for the influence of protein timing.
Methods: Twenty-four professional U23 cyclists (19 ± 1 years, peak oxygen uptake: 79.8 ± 4.9 ml/kg/min) participated in a six-day training camp. Participants were randomized to consume a protein supplement (40 g of casein) before sleep (n = 8) or in the afternoon (n = 8), or an isoenergetic placebo (40 g of carbohydrates) before sleep (n = 8). Indicators of fatigue/recovery (Hooper index, Recovery-Stress Questionnaire for Athletes, countermovement jump), body composition, and performance (1-, 5-, and 20-minute time trials, as well as the estimated critical power) were assessed as study outcomes.
Results: The training camp resulted in a significant (p < 0.001) increase in training loads (e.g. training stress score of 659 ± 122 per week during the preceding month versus 1207 ± 122 during the training camp), which induced an increase in fatigue indicators (e.g. time effect for Hooper index p < 0.001) and a decrease in performance (e.g. time effect for critical power p = 0.002). Protein intake was very high in all the participants (>2.5 g/kg on average), with significantly higher levels found in the two protein supplement groups compared to the placebo group (p < 0.001). No significant between-group differences were found for any of the analyzed outcomes (all p > 0.05).
Conclusions: Protein supplementation, whether administered before sleep or earlier in the day, exerts no beneficial effects during a short-term strenuous training period in professional cyclists, who naturally consume a high-protein diet.
{"title":"Pre-sleep protein supplementation in professional cyclists during a training camp: a three-arm randomized controlled trial.","authors":"Pedro L Valenzuela, Lidia B Alejo, Almudena Montalvo-Pérez, Diego Ojanguren, Miguel Górriz, Itziar Pagola, Laureano M Ozcoidi, Alejandro Lucia, David Barranco-Gil","doi":"10.1080/15502783.2023.2166366","DOIUrl":"https://doi.org/10.1080/15502783.2023.2166366","url":null,"abstract":"<p><strong>Background: </strong>The effects of pre-sleep protein supplementation on endurance athletes remain unclear, particularly whether its potential benefits are due to the timing of protein intake or solely to an increased total protein intake. We assessed the effects of pre-sleep protein supplementation in professional cyclists during a training camp accounting for the influence of protein timing.</p><p><strong>Methods: </strong>Twenty-four professional U23 cyclists (19 ± 1 years, peak oxygen uptake: 79.8 ± 4.9 ml/kg/min) participated in a six-day training camp. Participants were randomized to consume a protein supplement (40 g of casein) before sleep (n = 8) or in the afternoon (n = 8), or an isoenergetic placebo (40 g of carbohydrates) before sleep (n = 8). Indicators of fatigue/recovery (Hooper index, Recovery-Stress Questionnaire for Athletes, countermovement jump), body composition, and performance (1-, 5-, and 20-minute time trials, as well as the estimated critical power) were assessed as study outcomes.</p><p><strong>Results: </strong>The training camp resulted in a significant (p < 0.001) increase in training loads (<i>e.g</i>. training stress score of 659 ± 122 per week during the preceding month versus 1207 ± 122 during the training camp), which induced an increase in fatigue indicators (e.g. time effect for Hooper index p < 0.001) and a decrease in performance (e.g. time effect for critical power p = 0.002). Protein intake was very high in all the participants (>2.5 g/kg on average), with significantly higher levels found in the two protein supplement groups compared to the placebo group (p < 0.001). No significant between-group differences were found for any of the analyzed outcomes (all p > 0.05).</p><p><strong>Conclusions: </strong>Protein supplementation, whether administered before sleep or earlier in the day, exerts no beneficial effects during a short-term strenuous training period in professional cyclists, who naturally consume a high-protein diet.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2166366"},"PeriodicalIF":5.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9848340/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10581850","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}
Pub Date : 2023-01-01DOI: 10.1080/15502783.2022.2164209
Brandon M Roberts, Alexander L Kolb, Alyssa V Geddis, Marshall A Naimo, Ronald W Matheny
Background: Cellular inflammatory response, mediated by arachidonic acid (AA) and cyclooxygenase, is a highly regulated process that leads to the repair of damaged tissue. Recent studies on murine C2C12 cells have demonstrated that AA supplementation leads to myotube hypertrophy. However, AA has not been tested on primary human muscle cells. Therefore, the purpose of this study was to determine whether AA supplementation has similar effects on human muscle cells.
Methods: Proliferating and differentiating human myoblasts were exposed to AA in a dose-dependent manner (50-0.80 µM) for 48 (myoblasts) or 72 (myotubes) hours. Cell viability was tested using a 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay and cell counting; myotube area was determined by immunocytochemistry and confocal microscopy; and anabolic signaling pathways were evaluated by western blot and RT-PCR.
Results: Our data show that the treatment of primary human myoblasts treated with 50 µM and 25 µM of AA led to the release of PGE2 and PGF2α at levels higher than those of control-treated cells (p < 0.001 for all concentrations). Additionally, 50 µM and 25 µM of AA suppressed myoblast proliferation, myotube area, and myotube fusion. Anabolic signaling indicated reductions in total and phosphorylated TSC2, AKT, S6, and 4EBP1 in myoblasts at 50 µM of AA (p < 0.01 for all), but not in myotubes. These changes were not affected by COX-2 inhibition with celecoxib.
Conclusion: Together, our data demonstrate that high concentrations of AA inhibit myoblast proliferation, myotube fusion, and myotube hypertrophy, thus revealing potential deleterious effects of AA on human skeletal muscle cell health and viability.
{"title":"The dose-response effects of arachidonic acid on primary human skeletal myoblasts and myotubes.","authors":"Brandon M Roberts, Alexander L Kolb, Alyssa V Geddis, Marshall A Naimo, Ronald W Matheny","doi":"10.1080/15502783.2022.2164209","DOIUrl":"https://doi.org/10.1080/15502783.2022.2164209","url":null,"abstract":"<p><strong>Background: </strong>Cellular inflammatory response, mediated by arachidonic acid (AA) and cyclooxygenase, is a highly regulated process that leads to the repair of damaged tissue. Recent studies on murine C2C12 cells have demonstrated that AA supplementation leads to myotube hypertrophy. However, AA has not been tested on primary human muscle cells. Therefore, the purpose of this study was to determine whether AA supplementation has similar effects on human muscle cells.</p><p><strong>Methods: </strong>Proliferating and differentiating human myoblasts were exposed to AA in a dose-dependent manner (50-0.80 µM) for 48 (myoblasts) or 72 (myotubes) hours. Cell viability was tested using a 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay and cell counting; myotube area was determined by immunocytochemistry and confocal microscopy; and anabolic signaling pathways were evaluated by western blot and RT-PCR.</p><p><strong>Results: </strong>Our data show that the treatment of primary human myoblasts treated with 50 µM and 25 µM of AA led to the release of PGE<sub>2</sub> and PGF<sub>2α</sub> at levels higher than those of control-treated cells (<i>p</i> < 0.001 for all concentrations). Additionally, 50 µM and 25 µM of AA suppressed myoblast proliferation, myotube area, and myotube fusion. Anabolic signaling indicated reductions in total and phosphorylated TSC2, AKT, S6, and 4EBP1 in myoblasts at 50 µM of AA (<i>p</i> < 0.01 for all), but not in myotubes. These changes were not affected by COX-2 inhibition with celecoxib.</p><p><strong>Conclusion: </strong>Together, our data demonstrate that high concentrations of AA inhibit myoblast proliferation, myotube fusion, and myotube hypertrophy, thus revealing potential deleterious effects of AA on human skeletal muscle cell health and viability.</p>","PeriodicalId":17400,"journal":{"name":"Journal of the International Society of Sports Nutrition","volume":"20 1","pages":"2164209"},"PeriodicalIF":5.1,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9817121/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10507420","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}