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Creatine (Cr) supplementation increases muscle mass, strength, and power. Arginine [alpha]-ketoglutarate (A-AKG) is a precursor for nitric oxide production and has the potential to improve blood flow and nutrient delivery (i.e., Cr) to muscles. This study compared a commercial dietary supplement of Cr, A-AKG, glutamine, taurine, branched-chain amino acids, and medium-chain triglycerides with Cr alone or placebo on exercise performance and body composition. Thirty-five men (~23 yr) were randomized to Cr + A-AKG (0.1 g · kg[-1] · d[-1] Cr + 0.075 g · kg[-1] · d[-1] A-AKG, n = 12), Cr (0.1 g · kg[-1] · d[-1], n = 11), or placebo (1 g · kg[-1] · d[-1] sucrose, n = 12) for 10 d. Body composition, muscle endurance (bench press), and peak and average power (Wingate tests) were measured before and after supplementation. Bench-press repetitions over 3 sets increased with Cr + A-AKG (30.9 +/- 6.6 --> 34.9 +/- 8.7 reps; p < .01) and Cr (27.6 +/- 5.9 --> 31.0 +/- 7.6 reps; p < .01), with no change for placebo (26.8 +/- 5.0 --> 27.1 +/- 6.3 reps). Peak power significantly increased in Cr + A-AKG (741 +/- 112 --> 794 +/- 92 W; p < .01), with no changes in Cr (722 +/- 138 --> 730 +/- 144 W) and placebo (696 +/- 63 --> 705 +/- 77 W). There were no differences in average power between groups over time. Only the Cr-only group increased total body mass (79.9 +/- 13.0 --> 81.1 +/- 13.8 kg; p < .01), with no significant changes in lean-tissue or fat mass. These results suggest that Cr alone and in combination with A-AKG improves upper body muscle endurance, and Cr + A-AKG supplementation improves peak power output on repeated Wingate tests. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Firefighters operating in hot environments face challenges from protective garments that restrict heat dissipation, resulting in increased core temperature, thermal discomfort, and performance decline. Cooling vests represent a viable solution. The study aim was to compare effectiveness of the same amount of cooling power to the upper body (UB) or whole body (WB) in alleviating thermoregulatory and physiological stress, enhancing cognitive function, and reducing ratings of thermal discomfort and exertion, during 60 min of exercise in a hot environment (40°C, 40% relative humidity) while wearing firefighter turnout gear. METHODS: Eight healthy individuals (27.5 ± 3 y) participated in three conditions with either no cooling (Control) or active cooling with a liquid perfused shirt (UB cooling), or with a liquid perfused shirt and pants (WB cooling). In each trial, subjects performed three sets of 15 min of stepping (20 steps ⋅ min -1 ) and 5 min of rest. RESULTS: Both cooling strategies were beneficial compared to having no cooling at all. Subjects could only complete two exercise bouts during Control, but they completed all three bouts with active cooling. WB cooling provided an advantage over UB cooling for core and skin temperature, and thermal comfort and sensation. The advantage in minimizing the increase in core temperature was only evident during the third exercise bout. DISCUSSION: Active cooling is advantageous under these conditions. WB cooling provided some benefits vs UB cooling during heavy intensity exercise; however, it is uncertain whether these benefits would be observed during light-to-moderate exercise, which more likely reflects an actual firefighting scenario. Mansouri F, Talebian Nia M, Villar R, Cornish SM, Giesbrecht GG. Upper- vs. whole-body cooling during exercise with thermal protective clothing in the heat . Aerosp Med Hum Perform. 2024; 95(9):659-666.

Skeletal muscle plays an integral role in locomotion, but also as part of the integrative physiological system. Recent progress has identified crosstalk between skeletal muscle and various physiological systems, including the immune system. Both the musculoskeletal and immune systems are impacted by aging. Increased age is associated with decreased muscle mass and function, while the immune system undergoes "inflammaging" and immunosenescence. Exercise is identified as a preventative medicine that can mitigate loss of function for both systems. This review summarizes: (1) the inflammatory pathways active in skeletal muscle; and (2) the inflammatory and skeletal muscle response to unaccustomed exercise in younger and older adults. Compared to younger adults, it appears older individuals have a muted pro-inflammatory response and elevated anti-inflammatory response to exercise. This important difference could contribute to decreased regeneration and recovery following unaccustomed exercise in older adults, as well as in chronic disease. The current research provides specific information on the role inflammation plays in altering skeletal muscle form and function, and adaptation to exercise; however, the pursuit of more knowledge in this area will delineate specific interventions that may enhance skeletal muscle recovery and promote resiliency in this tissue particularly with aging., (© 2024 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

The serum concentration of cartilage oligomeric matrix protein (sCOMP) is considered a mechanosensitive biomarker of articular cartilage turnover, and N -propeptide of type II collagen (PIIANP), a proposed biomarker of type II collagen synthesis. Few studies have investigated the anabolic and turnover response of articular cartilage in response to acute changes in body mass during exercise. Using a repeated measure cross-over design, 15 healthy adults (age 18-30 years) performed three 30 min bouts of treadmill walking exercise under three loading conditions: (1) control (no alteration to body mass); (2) loaded (12% increase in body mass using a weighted vest); and (3) unloaded (12% decrease in body mass using lower body positive pressure). Venous blood was collected before, immediately after, and 15 and 30 min after exercise to investigate cartilage turnover (sCOMP) and anabolism (PIIANP). A main time effect ( p  ≤ 0.05) revealed that sCOMP levels were significantly greater post-exercise (for all three body loading conditions) as compared to before exercise, 15 and 30 min post-exercise. There was a significant condition × time interaction ( p  ≤ 0.05) for PIIANP, indicating that in the loaded condition, PIIANP concentrations at 15 min post-exercise were 13.8% greater than immediately following exercise, and 12.9% greater than before exercise. In summary, sCOMP concentration was acutely increased with all three loading conditions. However, PIIANP increased only after exercise in the loaded condition, suggesting an acute anabolic effect on articular cartilage. NCT05925244., Competing Interests: The authors declare that they have no conflicts of interest in relation to this study.

Context: Proper nutrition and exercise are effective strategies to improve overall metabolic health in diabetic patients., Objective: This study evaluated the effects of Nigella sativa (NS) supplementation during resistance training (RT) on some biochemical variables in type 2 diabetes patients., Methods: Forty patients were assigned to groups: RT + NS (RN), NS, RT + placebo (RP), and control (CO). RT was performed and NS was consumed for 8 weeks. Blood samples were collected at rest immediately before and after the 8 week intervention., Results: RT or NS by themselves reduced HOMA-IR, insulin, glucose, TG, TC, LDL, ESR, CRP, AST, ALT and ALP, and increased HDL and HOMA-S. The combination of RT and NS, rather than each intervention alone, had significant effects on reduction of HOMA-IR, insulin, ESR and CRP as well as increases in HDL, HOMA-β/S., Conclusion: RT combined with NS is sometimes a better strategy compared to single interventions for improving diabetes related biomarkers in type 2 diabetic patients.

Eccentric quasi-isometrics (EQIs) are a novel, low-velocity resistance exercise technique that incorporates a holding isometric contraction to positional fatigue, followed by voluntary resistance of the resulting eccentric muscle action. As females are typically more fatigue resistant than males during isometric and low-velocity dynamic muscle actions, this study explored sex-differences in the muscle fatigue response to an EQI protocol. Twenty-five ( n  = 12 female) participants completed 4 unilateral EQI elbow flexions. Absolute and relative surface electromyography (sEMG) amplitude (iEMG, LE peak), mean power frequency (MPF), angular impulse (aIMP), and elbow angle were compared across repetitions and between sexes using discrete values and statistical parametric/non-parametric mapping. There were significant and substantial sex and repetition differences in absolute iEMG, MPF, and aIMP, however, males and females had statistically similar absolute aIMP by repetition 4. When expressed relatively, there were no significant sex-differences. Additionally, there were significant between repetition changes in sEMG amplitude and elbow angle with an increasing number of repetitions, largely in the first-two thirds of repetition time. The current study suggests that there are absolute, but not relative sex-differences in EQI induced muscle fatigue, and the effects across repetitions occur predominately in the first two-thirds of repetition time.

Skeletal muscle is essential for human locomotion as well as maintaining metabolic homeostasis. Age-related reduction in skeletal muscle mass, strength, and function (i.e., sarcopenia) is a result of pathophysiological processes that include inflammation, alteration of molecular signaling for muscle protein synthesis and degradation, changes in insulin sensitivity, as well as altered skeletal muscle satellite cell activity. Finding strategies to mitigate skeletal muscle loss with age is deemed paramount as the percentage of the population continues to shift towards having more older adults with sarcopenia. Recent research indicates omega-3 fatty acid supplementation can influence anabolic or catabolic pathways in skeletal muscle. Our brief review will provide a synopsis of some underlying mechanisms that may be attributed to omega-3 fatty acid supplementation's effects on skeletal muscle. We will approach this review by focusing on cell culture, animal (pre-clinical models), and human studies evaluating omega-3 fatty acid supplementation, with suggestions for future research. In older adults, omega-3 fatty acids may possess some potential to modify pathophysiological pathways associated with sarcopenia; however, it is highly likely that omega-3 fatty acids need to be combined with other anabolic interventions to effectively ameliorate sarcopenia.

Concussion is a type of mild traumatic brain injury which results in symptoms within the physical, cognitive, emotional, and sleep domains. Historically, guidelines established by expert opinion have recommended rest during the initial stages of recovery following a concussion until symptom resolution. However, recent recommendations have shifted to advise an initial period of 24-48 h of rest immediately following concussion with the gradual introduction of light-to-moderate intensity aerobic exercise thereafter. Given the relatively recent transition in recommendations, the aim of this review is to provide an overview of the current literature on the efficacy of aerobic exercise following concussion. The current literature is limited to studies assessing the impact of standardized aerobic exercise following concussion. Upon review, literature suggests participating in aerobic exercise below the point of symptom exacerbation is safe in both the acute and chronic post-concussion symptom stages of recovery and does not delay time to medical clearance. Future large-scale randomized controlled trials assessing the impact of aerobic exercise and differences between males and females would help support the current evidence suggesting aerobic exercise could improve time to recovery following concussion and identify any sex differences in response. As well, future studies with the purpose of identifying optimal aerobic exercise volume and intensity in the treatment of concussion could improve the specificity of the current guidelines.

Osteoarthritis (OA) is a disease which results in degeneration of cartilage within joints and affects approximately 13.6% of adults over 20 years of age in Canada and the United States of America. OA is characterized by a state of low-grade inflammation which leads to a greater state of cellular catabolism disrupting the homeostasis of cartilage synthesis and degradation. Omega-3 polyunsaturated fatty acids (PUFAs) have been postulated as a potential therapeutic treatment option for individuals with OA. Omega-3 PUFAs are recognized for their anti-inflammatory properties, which could be beneficial in the context of OA to moderate pro-inflammatory markers and cartilage loss. The purpose of this narrative review is to outline recent pre-clinical and clinical evidence for the use of omega-3 in the management of OA.

Sarcopenia negatively affects skeletal muscle mass and function in older adults. Omega-3 (ω-3) fatty acid supplementation, with or without resistance exercise training (RET), is suggested to play a role as a therapeutic component to prevent or treat the negative effects of sarcopenia. A systematic review and meta-analysis were conducted on the impact of ω-3 fatty acid supplementation with or without RET on measures of muscle mass and function in older adults (≥55 y). The data sources included SPORTDiscus, PubMed, and Medline. All the study types involving ω-3 fatty acid supplementation on measures of muscle mass and function in older adults (without disease) were included. The mean differences (MDs) or standardized mean differences (SMDs) with 95% confidence intervals were calculated and pooled effects assessed. Sixteen studies (1660 females, 778 males) met our inclusion criteria and were included in the meta-analysis. ω-3 fatty acid supplementation did not impact lean tissue mass (SMD 0.09 [-0.10, 0.28]). Benefits were observed for lower body strength (SMD 0.54 [0.33, 0.75]), timed-up-and-go (MD 0.29 [0.23, 0.35]s), and 30-s sit-to-stand performance (MD 1.93 [1.59, 2.26] repetitions) but not walking performance (SMD -0.01 [-0.10, 0.07]) or upper body strength (SMD 0.05 [-0.04, 0.13]). Supplementing with ω-3 fatty acids may improve the lower-body strength and functionality in older adults.

While the vast majority of research involving creatine supplementation has focused on skeletal muscle, there is a small body of accumulating research that has focused on creatine and the brain. Preliminary studies indicate that creatine supplementation (and guanidinoacetic acid; GAA) has the ability to increase brain creatine content in humans. Furthermore, creatine has shown some promise for attenuating symptoms of concussion, mild traumatic brain injury and depression but its effect on neurodegenerative diseases appears to be lacking. The purpose of this narrative review is to summarize the current body of research pertaining to creatine supplementation on total creatine and phophorylcreatine (PCr) content, explore GAA as an alternative or adjunct to creatine supplementation on brain creatine uptake, assess the impact of creatine on cognition with a focus on sleep deprivation, discuss the effects of creatine supplementation on a variety of neurological and mental health conditions, and outline recent advances on creatine supplementation as a neuroprotective supplement following traumatic brain injury or concussion.

It is well established that creatine supplementation, primarily when combined with resistance training, significantly increases measures of muscle mass and performance (primarily strength). Emerging research also indicates that creatine supplementation may have favorable effects on measures of bone biology. These anabolic adaptations may be related to creatine influencing cellular hydration status, high-energy phosphate metabolism, growth factors, muscle protein kinetics, and the bone remodeling process. Accumulating research also suggests that creatine supplementation has anti-inflammatory and anti-catabolic properties, which may help create a favorable environment for muscle and bone accretion and recovery from exercise. Creatine supplementation has the ability to decrease markers of inflammation and possibly attenuate cancerous tumor growth progression. From a musculoskeletal perspective, there is some evidence to show that creatine supplementation reduces measures of muscle protein catabolism (primarily in males) and bone resorption when combined with resistance training. The purpose of this brief review is to summarize the current body of literature examining the potential anti-inflammatory and anti-catabolic effects of creatine supplementation across various research populations.

Purpose of Review: The age-related loss of skeletal muscle and bone tissue decreases functionality and increases the risk for falls and injuries. One contributing factor of muscle and bone loss over time is chronic low-grade inflammation. Exercise training is an effective countermeasure for decreasing the loss of muscle and bone tissue, possibly by enhancing immune system response. Herein, we discuss key interactions between the immune system, muscle, and bone in relation to exercise perturbations, and we identify that there is substantial "cross-talk" between muscle and bone and the immune system in response to exercise., Recent Findings: Recent advances in our understanding of the "cross-talk" between muscle and bone and the immune system indicate that exercise is likely to mediate many of the beneficial effects on muscle and bone via their interactions with the immune system. The age-related loss of muscle and bone tissue may be partially explained by an impaired immune system via chronic low-grade inflammation. Exercise training has a beneficial effect on immune system function and aging muscle and bone. Theoretically, the "cross-talk" between the immune system, muscle, and bone in response to exercise enhances aging musculoskeletal health.

Schwanbeck, SR, Cornish, SM, Barss, T, and Chilibeck, PD. Effects of training with free weights versus machines on muscle mass, strength, free testosterone, and free cortisol levels. J Strength Cond Res 34(7): 1851-1859, 2020-Free weights offer a more unstable training environment, which enhances muscle recruitment, whereas some machines have the advantage of using a "cam" pulley system that better matches strength curves. We compared the effect of training with free weights vs. machines on muscle mass, strength, free testosterone, and free cortisol concentrations. Forty-six subjects (26 women; 22 ± 3 years) were randomized to train using free weights or machines for 8 weeks (with each muscle group trained 2-3/weeks, 3-4 sets of 4-10 repetitions). Muscle thickness and strength were measured at 0 and 8 weeks. Salivary hormone concentrations were assessed before and at the end of workouts at the beginning, midway (4 weeks), and end (8 weeks) of the training intervention. Biceps and quadriceps muscle thickness increased (p < 0.01) with no difference between groups. There was a group × time interaction for machine bench press strength (p = 0.05) with the machine group increasing more than the free-weight group (13.9 vs. 8.6%). Free-weight bench press and squat, and Smith machine squat strength increased in both groups (11-19%; p < 0.01) with no difference between groups. Men in the free-weight group had a greater increase in free testosterone from before to after acute training sessions than men in the machine group and all women (p < 0.01); however, there was no differences between groups in free cortisol response to acute resistance exercise. Training sessions with free weights induced greater increases in free testosterone in men; however, training with free weights or machines resulted in similar increases in muscle mass and strength.

PURPOSE: This study was intended to determine the effect of skin cooling on breath-hold duration and predicted emergency air supply duration during immersion. METHODS: While wearing a helicopter transport suit with a dive mask, 12 subjects (29 ± 10 yr, 78 ± 14 kg, 177 ± 7 cm, 2 women) were studied in 8 and 20°C water. Subjects performed a maximum breath-hold, then breathed for 90 s (through a mouthpiece connected to room air) in five skin-exposure conditions. The first trial was out of water for Control (suit zipped, hood on, mask off). Four submersion conditions included exposure of the: Partial Face (hood and mask on); Face (hood on, mask off); Head (hood and mask off); and Whole Body (suit unzipped, hood and mask off). RESULTS: Decreasing temperature and increasing skin exposure reduced breath-hold time (to as low as 10 ± 4 s), generally increased minute ventilation (up to 40 ± 15 L · min -1 ), and decreased predicted endurance time (PET) of a 55-L helicopter underwater emergency breathing apparatus. In 8°C water, PET decreased from 2 min 39 s (Partial Face) to 1 min 11 s (Whole Body). CONCLUSION: The most significant factor increasing breath-hold and predicted survival time was zipping up the suit. Face masks and suit hoods increased thermal comfort. Therefore, wearing the suits zipped with hoods on and, if possible, donning the dive mask prior to crashing, may increase survivability. The results have important applications for the education and preparation of helicopter occupants. Thermal protective suits and dive masks should be provided. Madu VC, Carnahan H, Brown R, Ennis K-A, Tymko KS, Hurrie DMG, McDonald GK, Cornish SM, Giesbrecht GG. Skin cooling on breath-hold duration and predicted emergency air supply duration during immersion. Aerosp Med Hum Perform. 2020; 91(7):578-585.

Purpose: Resistance exercise induces muscle growth and is an important treatment for age-related losses in muscle mass and strength. Myokines are hypothesized as a signal conveying physiological information to skeletal muscle, possibly to "fine-tune" other regulatory pathways. While myokines are released from skeletal muscle following contraction, their role in increasing muscle mass and strength in response to resistance exercise or training is not established. Recent research identified both local and systemic release of myokines after an acute bout of resistance exercise. However, it is not known whether myokines with putative anabolic function are mechanistically involved in producing muscle hypertrophy after resistance exercise. Further, nitric oxide (NO), an important mediator of muscle stem cell activation, upregulates the expression of certain myokine genes in skeletal muscle., Method: In the systemic context of complex hypertrophic signaling, this review: (1) summarizes literature on several well-recognized, representative myokines with anabolic potential; (2) explores the potential mechanistic role of myokines in skeletal muscle hypertrophy; and (3) identifies future research required to advance our understanding of myokine anabolism specifically in skeletal muscle., Result: This review establishes a link between myokines and NO production, and emphasizes the importance of considering systemic release of potential anabolic myokines during resistance exercise as complementary to other signals that promote hypertrophy., Conclusion: Investigating adaptations to resistance exercise in aging opens a novel avenue of interdisciplinary research into myokines and NO metabolites during resistance exercise, with the longer-term goal to improve muscle health in daily living, aging, and rehabilitation.

Sarcopenia is an age-related muscle condition characterized by a reduction in muscle quantity, force generating capacity and physical performance. Sarcopenia occurs in 8-13% of adults ≥ 60 years of age and can lead to disability, frailty, and various other diseases. Over the past few decades, several leading research groups have focused their efforts on developing strategies and recommendations for attenuating sarcopenia. One potential nutritional intervention for sarcopenia is creatine supplementation. However, research is inconsistent regarding the effectiveness of creatine on aging muscle. The purpose of this perspective paper is to: (1) propose possible reasons for the inconsistent responsiveness to creatine in aging adults, (2) discuss the potential mechanistic actions of creatine on muscle biology, (3) determine whether the timing of creatine supplementation influences aging muscle, (4) evaluate the evidence investigating the effects of creatine with other compounds (protein, conjugated linoleic acid) in aging adults, and (5) provide insight regarding the safety of creatine for aging adults.

Sarcopenia, defined as the age-related decrease in muscle mass, strength and physical performance, is associated with reduced bone mass and elevated low-grade inflammation. From a healthy aging perspective, interventions which overcome sarcopenia are clinically relevant. Accumulating evidence suggests that exogenous creatine supplementation has the potential to increase aging muscle mass, muscle performance, and decrease the risk of falls and possibly attenuate inflammation and loss of bone mineral. Therefore, the purpose of this review is to: (1) summarize the effects of creatine supplementation, with and without resistance training, in aging adults and discuss possible mechanisms of action, (2) examine the effects of creatine on bone biology and risk of falls, (3) evaluate the potential anti-inflammatory effects of creatine and (4) determine the safety of creatine supplementation in aging adults.

Purpose: Blood flow restricted resistance exercise (BFR-RE) is an emerging hypertrophy training modality. A complete profile of its mechanisms of action has yet to be elucidated. Cytokines are universal intercellular messengers. Recent research has implicated certain cytokines (termed "myokines") in skeletal muscle hypertrophy pathways; however, little research has been conducted on the systemic myokine response to BFR-RE as potential hypertrophic biomarkers. Therefore, this project was conducted to determine any differences in the systemic myokine response between BFR-RE and control conditions., Methods: The appearance of systemic myokines interleukin-6 (IL-6), interleukin-15 (IL-15), and decorin were measured following acute bouts of low-load resistance exercise, BFR-RE, and high-load resistance exercise in physically active young males to determine if BFR-RE modifies the exercise-induced systemic myokine response., Results: No measurable levels of IL-6 were observed during the project. No significant effects were observed for IL-15. A significant time (11.91% increase pre to post exercise; p < 0.05) but no condition or condition by time effect was observed for decorin., Conclusion: These findings suggest that BFR-RE does not modify the systemic myokine appearance of IL-6, IL-15, or decorin when compared to control conditions.

The purpose of this study was to evaluate the effectiveness of 3.0 g/d of omega-3 fatty acid (eicosapentaenoic acid and docosahexaenoic acid) supplementation combined with progressive resistance training to improve body composition and lower inflammatory cytokines in older men when compared to placebo and resistance training. We hypothesized that completing a 12-week omega-3 supplementation period along with whole body resistance exercise (3 times/wk) would result in a significantly greater improvement in lean tissue mass as well as a significant decrease in interleukin-6 and tumor necrosis factor-α when compared to placebo. A total of 23 older men (≥65 years old) were randomized to an omega-3 supplementation group (n = 11) or placebo group (n = 12), and all the participants completed the same whole body progressive resistance training program. Baseline and 12-week data collection included body composition, muscle strength, functional ability, and inflammatory cytokines. Results indicated a significant main effect for time (all P < .05) for percent body fat (-2.5%), lean tissue mass (+1.1%), lumbar bone mineral density (+1.1%), hip bone mineral content (+1.1%), chest press strength (+31%), leg press strength (+37%), timed-up-and-go (-6.6%), and 6-minute walk distance (+4.5%) from baseline to post 12 weeks. No significant effects were noted for the 2 inflammatory cytokines measured (P > .05). We conclude that progressive resistance training exercise is an excellent method to enhance parameters of body composition, skeletal muscle strength, and functional ability in older men, whereas omega-3 supplementation did nothing to enhance these parameters or influence inflammatory biomarkers., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The purpose of this research was to identify if three different intensities of resistance exercise would acutely and differentially effect the systemic release of interleukin-6 (IL-6) and myoglobin in older men (≥65 years). A total of 11 older men performed isovolume resistance exercise on six different apparatuses at three different intensities (144 reps at 60%, 120 reps at 72%, and 108 reps at 80% of 1-repetition maximum), with the intensity order randomly allocated, to determine the systemic release of IL-6 and myoglobin in the blood. Blood samples were collected at six time points, including preexercise, immediately postexercise, and 3, 6, 24, and 48 hr postexercise. There were no differences between intensity levels; therefore, data for all conditions were pooled. IL-6 did not show any change from baseline values throughout all time points (p > .05), whereas myoglobin was elevated at 3, 6, and 24 hr postexercise and returned to baseline after 48 hr (p < .05).

The study purpose was to evaluate the effectiveness of creatine monohydrate supplementation (20 grams/day for 1 week and then 5 grams/day for 11 weeks) on inflammation (C-reactive protein, interleukin-1β, interleukin-6, s100 A8/A9, and tumor necrosis factor-α) and cartilage degradation (serum cartilage oligomeric matrix protein) in patients with knee osteoarthritis. We hypothesized that supplementing with creatine monohydrate for 12 weeks would lower biomarkers of inflammation and cartilage degradation in patients with knee osteoarthritis when compared to placebo. A total of 18 patients with mild to moderate knee osteoarthritis were recruited and randomized in a double blind fashion to either a creatine supplementation group (N = 9) or a placebo (N = 9). At baseline and after 12 weeks of supplementation patients had inflammatory and cartilage degradation biomarkers measured in the systemic blood. Further, patients completed the Knee injury and Osteoarthritis Outcome (KOOS) questionnaire as well as had their isometric thigh strength evaluated using an isokinetic dynamometer at both time points. Results indicated that there was no difference between the creatine and placebo groups at 12 week follow up in the inflammatory biomarkers measured nor was there any difference between the groups for cartilage degradation (all P>.05). No statistical differences were noted for the KOOS questionnaire subscales or total score (all P>.05). Muscle strength testing indicated a main effect of time for both groups where isometric thigh strength at 0° of knee flexion was lowered significantly (P=.047). No other significant differences were found in the strength data. We conclude that 12 weeks of supplementation with creatine monohydrate does not affect inflammatory biomarkers, cartilage degradation, KOOS scores, or muscle strength in patients with mild to moderate knee osteoarthritis., (Copyright © 2018. Published by Elsevier Inc.)

Activation of back musculature during work tasks leads to fatigue and potential injury. This is especially prevalent in dentists who perform much of their work from a seated position. We examined the use of an ergonomic dental stool with mid-sternum chest support for reducing lower back muscle activation. Electromyography of lower back extensors was assessed from 30 dental students for 20 s during three conditions in random order: (a) sitting upright at 90° of hip flexion on a standard stool, (b) leaning forward at 80° of hip flexion on a standard stool, and (c) leaning forward at 80° of hip flexion while sitting on an ergonomic stool. Muscular activity of the back extensors was reduced when using the ergonomic stool compared to the standard stool, by 33-50% (p < 0.01). This suggests a potential musculoskeletal benefit with use of a dental stool with mid-sternum chest support.

Position Statement: The International Society of Sports Nutrition (ISSN) presents this position based on a critical examination of the literature surrounding the effects of long-chain omega-3 polyunsaturated fatty acid (ω-3 PUFA) supplementation on exercise performance, recovery, and brain health. This position stand is intended to provide a scientific foundation for athletes, dietitians, trainers, and other practitioners regarding the effects of supplemental ω-3 PUFA in healthy and athletic populations. The following conclusions represent the official position of the ISSN: Athletes may be at a higher risk for ω-3 PUFA insufficiency.Diets rich in ω-3 PUFA, including supplements, are effective strategies for increasing ω-3 PUFA levels.ω-3 PUFA supplementation, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has been shown to enhance endurance capacity and cardiovascular function during aerobic-type exercise.ω-3 PUFA supplementation may not confer a muscle hypertrophic benefit in young adults.ω-3 PUFA supplementation in combination with resistance training may improve strength in a dose- and duration-dependent manner.ω-3 PUFA supplementation may decrease subjective measures of muscle soreness following intense exercise.ω-3 PUFA supplementation can positively affect various immune cell responses in athletic populations.Prophylactic ω-3 PUFA supplementation may offer neuroprotective benefits in athletes exposed to repeated head impacts.ω-3 PUFA supplementation is associated with improved sleep quality.ω-3 PUFA are classified as prebiotics; however, studies on the gut microbiome and gut health in athletes are currently lacking.

The aim of this cross-sectional study was to survey exercise specialists about nutrition counselling practices, their own dietary practices, and to identify potential relationships. An electronic survey was used to examine characteristics and strategies used for assessing and promoting healthy eating to clients. Exercise specialists (n = 94) were recruited through a public registry and through targeted advertising on 2 professional websites in Alberta, Canada. Eighty-five percent of respondents promoted healthy eating to clients. Confidence in assessing and promoting healthy eating was moderate to low. Those with more than 6 years of professional experience reported higher confidence compared with those with less than 1 year of experience in assessing healthy eating (P < 0.05) and promoting healthy eating (P < 0.01). Confidence was higher among those with more professional experience but who did not meet Canada's Food Guide recommendations (P < 0.05). Professional experience, personal dietary practices, and confidence are important characteristics when considering the assessment and promotion of healthy eating by exercise specialists. Promoting collaborative relationships between registered dietitians and exercise specialists would likely benefit exercise specialists when they are assessing and promoting healthy eating among their clients.

This research examined the changes in inflammatory cytokines interleukin 6 (IL-6), IL-1ß, IL-10, as well as muscle force, muscle soreness, thigh circumference, and range of motion in response to 3 bouts of eccentric knee extension. Ten males were recruited to participate. The participants performed eccentric exercise on 3 consecutive days on the knee extensors on the right leg separated by 24??h. Participants performed 6 sets of 10 repetitions of isokinetic eccentric knee extension at 120° per second. Blood was sampled before and after each exercise bout and 24?h after the final exercise bout. Muscle isometric force, delayed onset muscle soreness (DOMS), thigh circumference, and range of motion were evaluated before and after each exercise bout and 24?h after the final exercise bout. There were no statistically significant differences noted for the changes in isometric strength, thigh circumference, and range of motion, or IL-6 over the 4 days (all p > 0.05). On the second day and third day there was a significant increase noted in DOMS as compared with baseline (p < 0.05). These results suggest that 3 consecutive days of eccentric exercise results in DOMS but does not produce a sustained systemic inflammatory reaction or changes in muscle function.

Context: The natural health product, BeneFlax, is a standardized flaxseed [Linum usitatissimum L. (Linaceae)] lignan enriched product with evidence of product quality and known quantity of the bioactive component, lignan. The acceptance of this natural health product for its various health benefits requires greater evidence of its safety in the general population., Objective: We determined whether flaxseed lignan causes clinical hypoglycemia or hypotension in healthy older adults as an important aspect of safety., Materials and Methods: Participants aged 49-87 years were randomized in a double-blind trial to receive flaxseed lignan (543 mg/day in BeneFlax) or placebo while completing a 6-month walking program. The 94 participants who completed the study were stratified by age (<65 years versus ≥65 years) and treatment category to determine whether older adults were more susceptible to adverse effects., Results: After 6 months of treatment, average plasma glucose level (5.4 ± 0.6 mmol/L), systolic blood pressure (127 ± 14 mm Hg), and diastolic blood pressure (80 ± 9 mm Hg) were within normal clinical range. Controlling for sex and body mass index covariates resulted in no observed differences between plasma glucose or blood pressure measurements between treatment or age groups (p > 0.05). No incidents of hypoglycemia or hypotension were observed during BeneFlax treatment, suggesting that 543 mg falls at or below the no observable adverse effect level (NOAEL)., Discussion and Conclusion: These data suggest the flaxseed lignan product BeneFlax does not pose a risk of hypoglycemia or hypotension in healthy adults aged 49-87 years.

Sarcopenia, defined as the age-related loss of muscle mass, has a negative effect on strength, functional independence and overall quality of life. Sarcopenia is a multifactorial phenomenon characterized by changes in muscle morphology, protein and hormonal kinetics, oxidative stress, inflammation, physical activity and nutrition. It is well known that resistance exercise increases aging muscle mass and strength and these physiological adaptations from exercise may be further enhanced with certain nutritional interventions. Research indicates that essential amino acids and milk-based proteins, creatine monohydrate, essential fatty acids, and vitamin D may all have beneficial effects on aging muscle biology.

Peak aerobic power (VO2peak) is decreased after blood donation, but the time course for full recovery is unknown. We measured VO2peak and exercise time to fatigue before and weekly for 4 weeks after 450-ml blood donation at a blood donor clinic, to determine the time course of recovery. Twelve moderately active individuals (2 women, 10 men; 24.3 ± 5.2 years) of average aerobic fitness (based on their VO2peak relative to normative values) completed VO2peak exercise tests before donation, the day after donation, and at weekly intervals for 4 weeks after donation. VO2peak was determined by an incremental exercise test on a cycle ergometer. At baseline, mean absolute and relative VO2peak values were 4.06 ± 0.92 L·min(-1) and 46.6 ± 7.0 ml·kg(-1)·min(-1), respectively. VO2peak was significantly decreased on day 1 (3.85 ± 0.89 L·min(-1); 44.0 ± 6.5 ml·kg(-1)·min(-1)) and during week 2 (3.91 ± 0.97 L·min(-1); 44.5 ± 7.2 ml·kg(-1)·min(-1)) after blood donation (p < 0.05), and recovered at week 3 after donation. Time to fatigue and peak heart rate were not significantly affected by blood donation. We conclude that blood donation causes a significant decrease in VO2peak for between 2 and 3 weeks. The practical application of this study is that aerobic power in people of average fitness will be decreased, up to 3 weeks after donating blood. Despite this, there is no effect of blood donation on performance as measured by time to fatigue during an incremental test on a cycle ergometer.

The present study examined, using rats as a model, the effects of sex and age of exposure to dietary soya components on serum total and soya-specific antibody content. In Expt 1, Sprague-Dawley rats at 50 d of age were fed diets containing 20 % casein or 20 % alcohol-washed soya protein isolate (SPI) with or without supplemental isoflavones (ISF, 250 mg/kg diet) for 70, 190 or 310 d. The offspring were fed the same diets as their parents. In Expt 2, juvenile Sprague-Dawley rats at 30 d of age were fed diets containing 20 % casein with or without supplemental ISF (50 mg/kg diet) or increasing amounts of alcohol-washed SPI (5, 10 or 20 %) for 90 d. Exposure of rats to dietary SPI before the age of 28 d increased serum total IgA and IgM, and induced the production of SPI-specific IgA, IgG, IgM and IgE antibodies. Feeding of juvenile or adult rats with SPI elevated serum total IgA in females, while the opposite occurred in males, and markedly stimulated the production of SPI-specific IgM in females and IgG in males. Our data suggest that the effects of soya proteins and ISF on the production of serum total and SPI-specific antibodies appear to be sex dependent and also related to the age of exposure to soya in rats. However, the physiological significance of these immune responses remains to be determined.

We hypothesized that spinal manipulation (SM) would reduce strength imbalances between legs. Using an un-blinded randomized design, 28 males and 21 females (54 ± 19y) with at least a 15% difference in isometric strength between legs for hip flexion, extension, abduction, or knee flexion were randomized to treatment or placebo (mock spinal manipulation). Strength of the stronger and weaker legs for hip flexion, extension, abduction, and/or knee flexion was assessed before and after the intervention. SM reduced the relative strength difference between legs for knee flexion (mean ± SD 57 ± 53 to 5 ± 14%) and hip flexion (24 ± 12 to 11 ± 15%) compared to placebo (34 ± 29 to 24 ± 36%, and 20 ± 18 to 22 ± 26%, respectively) (p = 0.05). SM also improved strength in the weak leg for hip abduction (104 ± 43 to 116 ± 43 Nm) compared to placebo (84 ± 24 to 85 ± 31 Nm) (p = 0.03). This study suggests that spinal manipulation may reduce imbalances in strength between legs for knee and hip flexion.

We systematically reviewed the safety of physical activity (PA) for people with arthritis, osteoporosis, and low back pain. We searched PubMed, MEDLINE, Sport Discus, and the Cochrane Central Register of Controlled Trials (1966 through March 2008) for relevant articles on PA and adverse events. A total of 111 articles met our inclusion criteria. The incidence for adverse events during PA was 3.4%-11% (0.06%-2.4% serious adverse events) and included increased joint pain, fracture, and back pain for those with arthritis, osteoporosis, and low back pain, respectively. Recommendations were based on the Appraisal of Guidelines for Research and Evaluation, which applies Levels of Evidence based on type of study ranging from high-quality randomized controlled trials (Level 1) to anecdotal evidence (Level 4) and Grades from A (strong) to C (weak). Our main recommendations are that (i) arthritic patients with highly progressed forms of disease should avoid heavy load-bearing activities, but should participate in non-weight-bearing activities (Level 2, Grade A); and (ii) patients with osteoporosis should avoid trunk flexion (Level 2, Grade A) and powerful twisting of the trunk (Level 3, Grade C); (iii) patients with acute low back pain can safely do preference-based PA (i.e., PA that does not induce pain), including low back extension and flexion (Level 2, Grade B); (iv) arthritic patients with stable disease without progressive joint damage and patients with stable osteoporosis or low back pain can safely perform a variety of progressive aerobic or resistance-training PAs (Level 2, Grades A and B). Overall, the adverse event incidence from reviewed studies was low. PA can safely be done by most individuals with musculoskeletal conditions.

The purpose of this study was to determine the utility of dual-energy X-ray absorptiometry (DXA)-derived fat mass indices for predicting blood lipid profile in postmenopausal women. A secondary purpose was to determine whether waist circumference is comparable with DXA-derived measurements in predicting blood lipid profile. Subjects were 423 postmenopausal women (age 58.1 +/- 6.3 years). Fat mass was assessed at abdomen, trunk, and total body using DXA. Anthropometric measurements included BMI and waist circumference. Blood samples were analyzed for total cholesterol (TC), triglyceride (TAG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and cholesterol/HDL ratio. Of the DXA-derived measures, abdominal-fat mass was the best predictor of blood lipid profiles. DXA-derived abdominal fat mass and waist girth explained 20 and 16.5% of variation in TC/HDL ratio, respectively, in univariate analysis, with no difference between the slopes of the regression coefficients. Eighty-four percent of subjects were common to the top quartiles of waist circumference and abdominal fat mass, and blood lipid profiles generally worsened across increasing quartiles. DXA-derived abdominal fat mass and waist circumference are of equivalent utility for predicting alterations in blood lipids. Waist circumference is, therefore, ideal as an inexpensive means in primary health-care services for predicting risk of cardiovascular diseases in postmenopausal women.

A randomized double-blind placebo controlled study design was used to assess the effects of flaxseed lignan complex supplementation during exercise training on a metabolic syndrome composite score and osteoporosis risk in older adults. A total of 100 subjects (>or=50 years) were randomized to receive flaxseed lignan (543 mg.day-1 in a 4050 mg complex) or placebo while completing a 6 month walking program (30-60 min.day-1, 5-6 days.week-1). Fasting serum glucose, triacylglycerol (TAG), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein cholesterol, total cholesterol, interleukin-6, and tumor necrosis factor-alpha were measured every 2 months, while body composition, bone mineral density, and resting blood pressure were assessed at baseline and at 6 months. A composite Z score of 6 risk factors for metabolic syndrome (fasting glucose, HDL cholesterol, TAG, abdominal adiposity, blood pressure, and inflammatory cytokines) was calculated at baseline and at 6 months. Men taking placebo increased metabolic syndrome composite Z score (p < 0.05), but there were no changes in the other groups. A significant group x sex x time interaction was noted for TAG (p = 0.017) and diastolic blood pressure (p = 0.046), with men taking flaxseed lignan decreasing diastolic blood pressure relative to men taking placebo, and men taking placebo increasing TAG relative to men taking flax lignan. There were no differences between groups for change in bone measures, body composition, lipoproteins, or cytokines. Males taking the flaxseed lignan complex reduced metabolic syndrome score relative to men taking placebo, but a similar trend was not seen in females. Flaxseed lignan had no effect on bone mineral density or content, body composition, lipoproteins, glucose, or inflammation.

Increased inflammation with aging has been linked to sarcopenia. The purpose of this study was to evaluate the effects of supplementing older adults with alpha-linolenic acid (ALA) during a resistance training program, based on the hypothesis that ALA decreases the plasma concentration of the inflammatory cytokine tumor necrosis factor (TNF)-alpha and interleukin (IL)-6, which in turn would improve muscle size and strength. Fifty-one older adults (65.4 +/- 0.8 years) were randomized to receive ALA in flax oil (~14 g.day-1) or placebo for 12 weeks while completing a resistance training program (3 days a week). Subjects were evaluated at baseline and after 12 weeks for muscle thickness of knee and elbow flexors and extensors (B-mode ultrasound), muscle strength (1 repetition maximum), body composition (dual energy X-ray absorptiometry), and concentrations of TNF-alpha and IL-6. Males supplementing with ALA decreased IL-6 concentration over the 12 weeks (62 +/- 36% decrease; p = 0.003), with no other changes in inflammatory cytokines. Chest and leg press strength, lean tissue mass, muscle thickness, hip bone mineral content and density, and total bone mineral content significantly increased, and percent fat and total body mass decreased with training (p < 0.05), with the only benefit of ALA being a significantly greater increase in knee flexor muscle thickness in males (p < 0.05). Total-body bone mineral density improved in the placebo group, with no change in the ALA group (p = 0.05). ALA supplementation lowers the IL-6 concentration in older men but not women, but had minimal effect on muscle mass and strength during resistance training.

Purpose: The authors examined the combined effects of conjugated linoleic acid (CLA), creatine (C), and whey protein (P) supplementation during strength training., Methods: Sixty-nine participants (52 men, 17 women; M +/- SD age 22.5 +/-2.5 yr) were randomly assigned (double-blind) to 1 of 3 groups: CCP (6 g/d CLA + 9 g/d C + 36 g/d P; n = 22), CP (C + P + placebo oil; n = 25), or P (P + placebo oil; n = 22) during 5 wk of strength training (4-5 sets, 6-12 repetitions, 6 d/wk). Measurements were taken for body composition (air-displacement plethysmography), muscle thickness (ultrasound) of the flexors and extensors of the elbow and knee, 1-repetition-maximum (1-RM) strength (leg press and bench press), urinary markers of bone resorption (N-telopeptides, NTx), myofibrillar protein catabolism (3-methylhistidine; 3-MH), oxidative stress (8-isoprostanes), and kidney function (microalbumin) before and after training., Results: Contrast analyses indicated that the CCP group had a greater increase in bench-press (16.2% +/- 11.3% vs. 9.7% +/- 17.0%; p < .05) and leg-press (13.1% +/- 9.9% vs. 7.7% +/-14.2%; p < .05) strength and lean-tissue mass (2.4% +/- 2.8% vs. 1.3% +/-4.1%; p < .05) than the other groups combined. All groups increased muscle thickness over time (p < .05). The relative change in 3-MH (CCP -4.7% +/- 70.2%, CP -0.4% +/- 81.4%, P 20.3% +/- 75.2%) was less in the groups receiving creatine (p < .05), with the difference for NTx also close to significance (p = .055; CCP -3.4% +/- 66.6%, CP -3.9% +/- 64.9%, P 26.0% +/- 63.8%). There were no changes in oxidative stress or kidney function., Conclusion: Combining C, CLA, and P was beneficial for increasing strength and lean-tissue mass during heavy resistance training.

Exercise has a beneficial effect on bone, possibly by stimulating estrogen receptor alpha. Because estrogen up-regulates this receptor, estrogen therapy combined with exercise training may be optimal for increasing bone mineral density. Studies combining estrogen therapy and exercise training in postmenopausal women show mixed results, but indicate that the combination of interventions may be more effective for increasing bone mass than either intervention alone. Plant-like estrogens (i.e phytoestrogens such as soy isoflavones) may act as weak estrogen agonists or antagonists, have small beneficial effects on bone, and may interact with exercise for increasing bone mineral density. Phytoestrogen derived from flaxseed (flax lignans) has not been evaluated as extensively as soy isoflavones and thus its effect on bone is difficult to determine. Estrogen or soy isoflavones given to postmenopausal women results in a small increase in lean tissue mass that may be mediated through estrogen receptor alpha on muscle or through decreased inflammation.

Aim: Creatine monohydrate supplementation is beneficial for enhancing high-intensity exercise performance, especially activities that involve repeated sprints. Creatine monohydrate supplementation is common in ice-hockey players. The purpose of this study was to determine the effect of creatine monohydrate supplementation on sprint skating performance in Junior B and collegiate ice-hockey players., Methods: Seventeen ice-hockey players were randomly assigned to receive creatine (0.3 g/kg body mass/day for 5 days) or placebo. Before and after supplementation players performed repeated sprints to exhaustion on a skating treadmill (repeated 10-s sprints; 30-s rest between sprints) while blood lactate was simultaneously collected. The time to exhaustion on the treadmill test was calculated as total amount of time, including partial intervals, before the player reached exhaustion. Players were also tested for peak torque and average power during knee extension/flexion (3 sets of 10 reps; 60-s rest between sets) on an isokinetic dynamometer at 60 degrees/s., Results: The change in time to exhaustion from before to after supplementation averaged 20.6+/-7 s in the creatine group and 21.9+/-13 s in the placebo group, with no differences between groups. Likewise, there were no differences between groups for changes in isokinetic peak torque and average power. There were no differences between groups over time for blood lactate changes during the repeated sprints on the treadmill., Conclusions: We conclude that creatine was not effective for improving performance in these ice-hockey players.

A paired pulse stimulation protocol was employed to examine the loss of inhibition in the hippocampus of the kainic acid-treated rat in vivo. Extracellular recordings were obtained from the CA1 pyramidal cell layer 1, 4, 8 and 16 weeks after a unilateral intracerebroventricular injection of kainic acid. Recordings were made both ipsilateral and contralateral to the site of kainic acid injection. The results demonstrated a loss of paired pulse inhibition in hippocampal CA1 area ipsilateral to the site of kainic acid injection which did not alter over 16 weeks. While the contralateral hippocampus showed no change 1 week after kainic acid injection, a reduction of paired pulse inhibition was seen after 4, 8 and 16 weeks. It is therefore apparent that the effects of kainic acid on the state of inhibition of the hippocampus are long-lasting and, furthermore, that the response to an injection of kainic acid is widespread, affecting the inhibitory control of the contralateral hippocampus.