Regular Use of Cannabis in Female Athletes Is Associated With a Reduction in Early Anaerobic Power Production.

ABSTRACT: Lisano, JK, Flores, VA, Kisiolek, JN, and Stewart, LK. Regular use of cannabis in female athletes is associated with a reduction in early anaerobic power production. J Strength Cond Res 37(3): 616-622, 2023-Despite a growing number of claims related to the ability of cannabis use to affect health and performance, there is limited research available, especially in female athletes. This cross-sectional study aimed to determine whether chronic cannabis use in physically active female athletes is related to altered health and performance. Healthy, physically active, female cannabis users (CU: n = 12) and noncannabis users (NU: n = 12) with an average age of 23.8 ± 3.7 years and 19.3 ± 4.2% body fat completed athletic performance and health assessments. Significance was set at alpha = 0.05. The age of onset of regular cannabis use was 20.1 ± 2.8 years in CU with an average duration of cannabis use of 5.8 ± 3.1 years. There were no differences between groups with respect to body size, body composition, pulmonary function, cardiorespiratory function, or muscular strength. Cannabis users produced significantly less power in the first 2 stages of the Wingate assessment, but CU experienced significantly less anaerobic fatigue. Although body composition and cardiovascular fitness were comparable, average C-reactive protein concentration classified CU with higher risk for cardiovascular disease (CVD). Athletes and coaches who rely heavily on anaerobic performance should consider these findings because they indicate that regular cannabis use may affect early power production and CVD risk.

Updated Systematic Review and Quantitative Synthesis of Physical Activity Levels in Multiple Sclerosis.

OBJECTIVE: This article provided an updated quantitative synthesis of physical activity levels in persons with multiple sclerosis compared with controls and other clinical populations. DESIGN: A systematic search through PubMed, Scopus, and PsycINFO was conducted for articles published between August 2016 and July 2022. Articles that included a group comparison of at least one measurement of physical activity between adults with multiple sclerosis and controls or other clinical populations were included in the meta-analysis. RESULTS: Twenty-four studies met the inclusion criteria and yielded a total of 119 comparisons. There was a moderate difference in physical activity levels between persons with multiple sclerosis and controls (effect size = -0.56, P < 0.01), but no significant difference between persons with multiple sclerosis and other clinical populations (effect size = 0.01, P = 0.90). The pooled effect sizes comparing multiple sclerosis with controls ( Q104 = 457.9, P < 0.01) as well as with clinical populations ( Q13 = 108.4, P < 0.01) were heterogeneous. Moderating variables included sex, disability status, measurement method, outcome, intensity, and application of a multiple sclerosis-specific cut-point. CONCLUSIONS: Physical activity levels remain significantly lower in persons with multiple sclerosis compared with controls, but the magnitude of difference has become smaller over the past decade. There is a need for continued development of effective physical activity programs that can reach the greater community with multiple sclerosis.

Effects of aerobic, resistance, and combined exercise training on health-related quality of life in multiple sclerosis: Systematic review and meta-analysis.

BACKGROUND: Multiple sclerosis (MS) is an immune-mediated, neurodegenerative disease of the central nervous system that manifests in symptoms that compromise health-related quality of life (HRQOL). HRQOL focuses on a person's overall, subjective evaluation of health status primarily in the physical and mental domains. Exercise training is a form of rehabilitation for managing MS-related outcomes that might influence HRQOL. Reviews on exercise training are available, but we are unaware of a recent comprehensive review and meta-analysis of exercise effects for improving physical and mental domains of HRQOL. This analysis provides an updated review and meta-analysis of randomized controlled trials (RCTs) examining interventions consisting of aerobic, resistance and combined exercise training for improving HRQOL in persons with MS. This systematic review 1) assessed the overall strength of evidence for exercise interventions on HRQOL, 2) evaluated the relative effect of exercise interventions on physical and mental domains of HRQOL, and 3) determined moderators of exercise intervention effects on HRQOL. METHODS: Seven databases were searched for RCTs evaluating physical and/or mental domains of HRQOL with adults diagnosed with MS and undergoing an intervention of aerobic, resistance or combined exercise training compared with a non-exercise comparator. Data extraction included participant and intervention characteristics, and pre- and post-intervention HRQOL outcome data. Effect sizes (ESs) were calculated as standardized mean differences (SMDs) and a multilevel random-effects model was used to generate an aggregated SMD that compared exercise with non-exercise control conditions. RESULTS: Twelve RCTs met the inclusion criteria and yielded 23 ESs to be analyzed. Participants (N = 593; 308 intervention vs. 285 control conditions) had a mean (±standard deviation) age of 42.4 (6.5) years and 80% (18.3%) were female. Results generated a medium effect of exercise for improving overall HRQOL (ES=0.64, p = 0.0001) with high heterogeneity (Q11=58.8, I2=86.7%). Exercise training yielded a large effect on the physical domain (k = 12, ES=0.82, p<0.0009) and a medium effect on the mental domain (k = 11, ES=0.41, p<0.0001). Moderator analyses identified exercise modality, supervision level, intervention delivery and length, HRQOL tool, and number of participants with relapsing-remitting MS as significant influences of ES for HRQOL. CONCLUSIONS: Exercise training is clinically effective for improving overall HRQOL in MS and produces greater improvements in the physical domain of HRQOL than the mental domain. The moderator analysis suggests that supervised, aerobic, and group-delivered exercise training of ≥3 months yields the most influence on HRQOL. Such results may have major implications for MS treatment and care.

Systematic review and meta-analysis of sedentary behavior in persons with multiple sclerosis.

BACKGROUND: Persons with multiple sclerosis (MS) engage in less physical activity than the general population, and the disease manifestations and comorbidity conditions might further predispose them toward sedentary behavior (SB) among this population. We performed a systematic review with meta-analysis of studies that compared SB in persons with MS and non-MS controls, and examined factors that may moderate the difference in SB between the two groups. METHODS: We conducted a systematic search using PubMed, PsycINFO, Scopus, and CINAHL from inception up to August 2022, and identified studies that involved group comparison of SB outcomes between MS and non-MS controls. Effect sizes were calculated as standardized mean differences (SMDs) using Hedge's g. We generated a multilevel random-effects model for estimating an overall effect, and performed moderator analyses. Methodological quality was assessed using the Appraisal Tool for Cross-Sectional Studies (AXIS tool). RESULTS: Eleven studies were included (1403 MS vs. 449 controls) and yielded 17 effects for meta-analysis. Results indicated an overall small, but significant effect (SMD [95% CI] = 0.27 [0.02, 0.53], p = 0.03) with significant heterogeneity (Q16 = 72.2, p < 0.01; I2total = 75.8%). There were larger effects when the MS sample had a higher proportion of females, or when SB was reported as percent sedentary time per day compared with other SB outcomes (p = 0.03 and 0.05, respectively). The included studies achieved fairly good quality (91.4%) using the AXIS tool. CONCLUSIONS: The cumulative evidence supports that persons with MS engage in more SB than non-MS controls. Our findings may support the design of targeted behavioral change interventions for reducing SB and improving health and function in the MS population.

Eight Weeks of Daily Cannabidiol Supplementation Improves Sleep Quality and Immune Cell Cytotoxicity.

BACKGROUND: The endocannabinoid system is active in nervous and immune cells and involves the expression of two cannabinoid receptor genes (CB1 and CB2), along with endogenous endocannabinoid ligands, 2-arachidonoyl glycerol (2-AG) and arachidonoyl ethanolamide (anandamide), and their synthetic enzymes. Cannabidiol (CBD) is a non-intoxicating exogenous cannabinoid agonist derived from plants that, at high doses, has received FDA approval as an anticonvulsant for epileptic seizures, and at low doses is marketed as a food-grade supplement for improved mental health, sleep quality, and immunological function. At present, the predominance of published CBD clinical research has focused on ameliorative or disease-specific intervention, with few trials investigating CBD effects in healthy populations. METHODS: This clinical study aimed to investigate the effects of 8 weeks of 50 mg oral CBD on mental health, sleep quantity and quality, and immune cell function in healthy, college-aged individuals. Twenty-eight participants (average age 25.9 ± 6.1 y) were randomized to receive either daily oral capsules of 50 mg of CBD (CB, n = 14) or a calorie-matched placebo (CN, n = 14). Participants completed pre- and post-intervention assessments, including anthropometric measurements, mental health surveys, sleep analysis, and immunological function assessments. RESULTS: After completing the 8-week intervention, there were no significant changes in body weight and BMI (CN: 1.09 ± 0.89%: CB: 1.41 ± 1.07%), or body fat percentage (CN: 9.01 ± 7.51%: CB: 8.57 ± 7.81%), respectively (values are % change pre to post, p > 0.05). There were also no significant differences between CB and CN groups with respect to mental health measures, sleep quantity, or circulating immunophenotype as a result of the intervention. However, the CB group experienced significant improvements in sleep quality measured objectively using a sleep questionnaire (p = 0.0023) and enhanced Natural Killer (NK) immune cell function assessed in situ (p = 0.0125). CONCLUSIONS: Eight weeks of daily 50 mg CBD may improve sleep quality, and NK immunosurveillance in healthy, younger adults.

Effects of Oral Cannabidiol on Health and Fitness in Healthy Adults: An 8-Week Randomized Trial.

BACKGROUND: There is a lack of research on the effects of cannabidiol (CBD) on health-related fitness, physical activity, cognitive health, psychological wellbeing, and concentrations of C-reactive protein (CRP) in healthy individuals. CBD has potential anti-inflammatory and neuroprotective effects. METHODS: This study aimed to investigate the effects of 8 weeks of CBD on the above-mentioned measures in healthy individuals. Forty-eight participants were randomized into two groups receiving either oral capsules of 50 mg of CBD or a calorie-matched placebo daily. Participants completed pre- and post-intervention assessments, including blood draws, body composition, fitness, physical activity, and self-reported surveys. RESULTS: There were no significant differences between groups regarding body composition, aerobic fitness, muscular strength, physical activity, cognitive health, psychological wellbeing, and resting CRP concentrations. However, the placebo group experienced a decline in mean peak power and relative peak power compared to the CBD group. CONCLUSIONS: The results suggest that 8 weeks of CBD supplementation may prevent declines in anaerobic fitness over time. However, long-term CBD supplementation may not be beneficial for altering measures of health-related fitness, mental health, and inflammation in healthy individuals.