Polycystic ovary syndrome (PCOS) increases type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) with insulin resistance. We hypothesized that a 35 g whey preload would improve insulin sensitivity and glucose handling while reducing biomarkers associated with NAFLD. Twenty-nine age-matched women (CON = 15, PCOS = 14) completed oral glycemic tolerance tests following baseline (Day 0) as well as an acute (Day 1) and short-term whey supplementation (Day 7). Whey had an interaction effect on glucose (p = 0.02) and insulin (p = 0.03), with glucose remaining stable and insulin increasing with whey supplementation. Insulin sensitivity (p < 0.01) improved with whey associated with increased glucagon secretion (p < 0.01). Alanine aminotransferase (ALT), and aspartate aminotransferase (AST) remained unchanged, but “day” had an effect on the AST:ALT ratio (p = 0.04), whereas triglycerides and sex hormone binding globulin overall were greater in the PCOS group (p < 0.05). Total cholesterol decreased in PCOS (by 13%) and CON (by 8%) (NS). HepG2 cells treated with plasma from participants before and after whey decreased lipid accumulation in the PCOS group after whey (p < 0.05). Whey provided an insulinogenic and glycemic homeostatic effect in women with PCOS with the potential to combat NAFLD-consequences.
Ageing is an escalating global health issue, with the World Health Organization (WHO) reporting that one in six individuals will be 60 years or older by the year 2030. Therefore, understanding the mechanisms of complex biological ageing processes and associated healthcare challenges has become increasingly important. Intrinsic capacity (IC), defined by WHO as the composite of all physical and mental capacities an individual possesses, can be used as a proxy for defining healthy ageing. IC has five key components: locomotion, cognition, psychological, sensory, and vitality capacity (VC). This review paper specifically focuses on exercise as an effective tool to preserve VC in ageing populations. The physiological domains of VC discussed include energy and metabolism, neuromuscular function, immune and stress response, mitochondrial function, and the methylation clock. Additionally, we highlight potential outcome measures for assessing each of these domains. This review also covers areas of focus for future research and possible interventions. We ultimately conclude that ageing is a complex, multifaceted process resulting in deficits across multiple VC components. However, regular exercise is capable of producing physiological adaptations that may be beneficial in the context of healthy ageing and improving or preserving the status of VC components.
Proper training methods may be used as an effective preventative measure for many of the musculoskeletal injuries sustained as a first responder that are inherent to the profession. The traditionally low fitness levels and poor exercise habits of city firefighters may predispose this population to an increased risk of chronic conditions, such as cardiovascular and metabolic disease. The purpose of this study was to analyze changes in the health and fitness parameters of professional firefighters across North Texas during a six-month training program. Twenty-two professional firefighters completed six months of group training, consisting of two training sessions per week. These individuals underwent a pre- and post-fitness testing protocol that consisted of body composition, range of motion, anaerobic power, muscular endurance, and cardiorespiratory fitness. Improvements (p < 0.05) in flexibility, anaerobic performance, fatigue index, muscular endurance, and aerobic fitness were found following the six-month training program. No differences in body composition or peak power were observed (p > 0.05). Six months of group exercise improves aerobic and anaerobic fitness, exercise tolerance, muscular endurance, and flexibility in firefighters.
Proper monitoring of fatigue and muscular damage may be used to decrease the high levels of cardiovascular disease, overuse musculoskeletal injuries, and workers compensation claims within the profession of firefighting. The purpose of this study was to examine muscle damage, muscular fatigue, and inflammation responses following a typical firefighting shift. Twenty-four professional firefighters completed two Physical Ability Tests to standardize the tasks typically performed in a day of work, and to elicit similar physiological responses. Participants were then monitored for 48 h. Prior to, and 48 h following the Physical Ability Tests, participants were evaluated for changes in strength, power, range-of-motion, as well as blood markers including myoglobin and c-reactive protein. Following the Physical Ability Tests, significant differences in myoglobin (p < 0.05), grip strength (p < 0.05), vertical jump (p < 0.05), and sit-and-reach (p < 0.05) were observed. No difference in c-reactive protein was observed (p > 0.05). After 24 hours following a shift, firefighters exhibited decreased strength, power, and range-of-motion. This may lead to decreases in performance and an increased risk of injury.
Ageing negatively affects quality of life and healthspan, and interventions are needed to slow this progressive decline. Previously, we have demonstrated the potential functional benefits of combining a genetically modified probiotic (GMP) targeting the non‐canonical arm of the renin–angiotensin system (RAS) with exercise training. Initial RNAseq studies indicated the potential of the interventions to influence circadian physiology. Therefore, the objective of this study was to evaluate the expression of circadian‐related genes in the tibialis anterior and soleus muscles in male and female aged rats in response to the administration of the GMP, exercise training and multiple controls. Following 12 weeks of the intervention, circadian‐related genes were differentially expressed in male and female aged rats and between tissues, primarily influenced by the exercise intervention, with potential additive effects of the GMP. Several genes were also significantly associated with measures of physical performance. Thus, combining exercise with a RAS‐related GMP may have potential functional benefits in late life, potentially related to circadian‐related impacts within skeletal muscle.