Resistance-exercise training attenuates LPS-induced astrocyte remodeling and neuroinflammatory cytokine expression in female Wistar rats

Neuroinflammation is an early detectable marker of mild cognitive impairment, the transition state between normal cognition and dementia. Resistance-exercise training can attenuate the cognitive decline observed in patients with mild cognitive impairment. However, the underlying mechanisms of resistance training effects are largely unknown. To further elucidate mechanisms of the known cognitive health benefits from resistance-exercise training, we tested if three weeks of resistance-exercise training could ameliorate lipopolysaccharide-induced neuroinflammation. Five-week-old female Wistar rats received intracerebroventricular injections of lipopolysaccharides to induce neuroinflammation and cognitive impairment. Rats then underwent three weeks of progressive ladder climbing to recapitulate resistance-exercise training in humans. Cognition was assessed towards the end of the training period by novelty object recognition testing. Neuroinflammation was measured one and 24-hours after the last resistance-exercise training workout. Resistance-exercise training ameliorated cognitive impairment, diminished lipopolysaccharide-induced neuroinflammatory cytokine expression, and attenuated astrocyte remodeling in the dentate gyrus 24-hours post exercise. Here, we provide evidence that the ladder-climbing model of resistance-exercise training in rats can improve cognition as early as three weeks. Additionally, these data support the hypothesis that resistance exercise can reduce lipopolysaccharide-induced neuroinflammation in the dentate gyrus.

Exploring the Effects of Greek Yogurt Supplementation and Exercise Training on Serum Lithium and Its Relationship With Musculoskeletal Outcomes in Men

Dairy products can act as a dietary source of lithium (Li), and a recent study in university-aged males demonstrated that Greek yogurt (GY) supplementation augmented gains in fat free mass, strength and bone formation after 12 weeks of resistance exercise training compared to carbohydrate (CHO) pudding supplementation. Here, we performed secondary analyses to explore whether GY would alter serum Li levels and whether changes in serum Li would associate with changes in body composition, strength, and bone turnover markers. Results show that the GY group maintained serum Li levels after exercise training, whereas the CHO group did not. Maintaining/elevating serum Li levels was also associated with greater gains in strength and reductions in bone resorption. However, controlling for other dietary factors in GY such as protein and calcium weakened these associations. Thus, future studies should assess the causative role, if any, of dietary Li alone on strength and bone resorption in humans.

Resistance Exercise and Whey Protein Supplementation Reduce Mechanical Allodynia and Spinal Microglia Activation After Acute Muscle Trauma in Rats

Muscle injury caused by direct trauma to the skeletal muscle is among the main musculoskeletal disorders. Non-pharmacological treatments have been effective in controlling muscle injury–induced pain; however, there are just a few studies in the literature investigating this response. Thus, the present study aimed to evaluate the effect of a resistance exercise training protocol combined or not with whey protein supplementation on mechanical allodynia induced by muscle injury. In addition, we also investigated the involvement of spinal glial cells in this process. For this purpose, male Wistar rats underwent a muscle injury model induced by direct trauma to the gastrocnemius muscle. Mechanical allodynia was measured by a digital von Frey algesimeter test. To evaluate the effect of exercise and/or supplementation on mechanical allodynia, the animals practiced exercises three times a week for 14 days and received supplementation daily for 14 days, respectively. Moreover, the effect of both the participation of spinal glial cells in the muscle injury and the resistance exercise training and/or whey protein supplementation on these cells was also investigated by the Western blot assay. The results demonstrated that resistance exercise training and whey protein supplementation, combined or alone, reduced mechanical allodynia. These treatments also reduced the number of interstitial cells and pro-inflammatory cytokine IL-6 levels in the injured muscle. It was also found that spinal microglia and astrocytes are involved in muscle injury, and that resistance exercise training combined with whey protein supplementation inhibits spinal microglia activation. The results suggest that both resistance exercise training and whey protein supplementation may be effective non-pharmacological treatments to control pain in the muscle after injury induced by acute trauma.

Aerobic versus resistance exercises on systemic inflammation and sleep parameters in obese subjects with chronic insomnia syndrome

Background: Chronic primary insomnia is a prevalent sleep disorder that is associated with adverse effects on health out- comes. Exercise is often considered a non-pharmacological approach that could have beneficial effects on sleep. Objective: The aim of the study was to compare the impact of aerobic and resistance exercise training on quality of sleep and inflammatory markers among subjects with chronic primary insomnia. Material and Methods: Sixty previously sedentary subjects with chronic primary insomnia subjects enrolled in this study, their age ranged from 31-52 years. All participants were randomly assigned to aerobic exercise intervention group (group A, n=35) or resistance exercise intervention group (group B, n=35). Polysomnographic recordings for sleep quality assessment, IL-6, IL-10 and TNF-α were measured before and at the end of the study after six months. Results: There was a significant increase in the total sleep duration, sleep efficiency, sleep onset latency and IL-10 in group(A) and group (B) in addition to significant reduction in awake time after sleep onset, REM latency, IL-6 and TNF-α after 6 months of aerbic and resistance exercise training. However, there were significant differences between both groups at the end of the study. Conclusion: Aerobic exercise training is more appropriately than resistance exercise training in modulation of inflammatory and sleep quality among subjects with chronic primary insomnia. Keywords: Aerobic exercise; chronic primary insomnia; inflammatory cytokines; resistance exercise; sleep quality.

Muscle Protein Synthesis and Muscle/Metabolic Responses To Resistance Exercise Training in South Asian and White European Men

PurposeThe aims of the current study, therefore, were to compare 1) free-living MPS and 2) muscle and metabolic adaptations to resistance exercise in South Asian and white European adults.MethodsEighteen South Asian and 16 White European men were enrolled in the study. Free-living muscle protein synthesis was measured at baseline. Muscle strength, body composition, resting metabolic rate, VO2max and metabolic responses (insulin sensitivity) to a mixed meal were measured at baseline and following 12 weeks of resistance exercise training. Results Free-living muscle protein synthesis was not different between South Asians (1.48 ± 0.09 %/day) and White Europeans (1.59 ± 0.15 %/day) (p=0.522). In response to resistance exercise training there were no differences, between South Asians and White Europeans, muscle mass, lower body strength or insulin sensitivity. However, there were differences between the ethnicities in response to resistance exercise training in body fat, resting carbohydrate and fat metabolism, blood pressure, VO2max and upper body strength with responses less favourable in South Asians. ConclusionIn this exploratory study there were no differences in muscle protein synthesis or anabolic and metabolic responses to resistance exercise, yet there were less favourable responses in several outcomes. These findings require further investigation.

Skeletal Muscle Quality: A Biomarker for Assessing Physical Performance Capabilities in Young Populations

Muscle quality (MQ), defined as the amount of strength and/or power per unit of muscle mass, is a novel index of functional capacity that is increasingly relied upon as a critical biomarker of muscle health in low functioning aging and pathophysiological adult populations. Understanding the phenotypical attributes of MQ and how to use it as an assessment tool to explore the efficacy of resistance exercise training interventions that prioritize functional enhancement over increases in muscle size may have implications for populations beyond compromised adults, including healthy young adults who routinely perform physically demanding tasks for competitive or occupational purposes. However, MQ has received far less attention in healthy young populations than it has in compromised adults. Researchers and practitioners continue to rely upon static measures of lean mass or isolated measures of strength and power, rather than using MQ, to assess integrated functional responses to resistance exercise training and physical stress. Therefore, this review will critically examine MQ and the evidence base to establish this metric as a practical and important biomarker for functional capacity and performance in healthy, young populations. Interventions that enhance MQ, such as high-intensity stretch shortening contraction resistance exercise training, will be highlighted. Finally, we will explore the potential to leverage MQ as a practical assessment tool to evaluate function and enhance performance in young populations in non-traditional research settings.