Autophagy and Aging: Maintaining the Proteome through Exercise and Caloric Restriction

Accumulation of dysfunctional and damaged cellular proteins and organelles occursduring aging, resulting in a disruption of cellular homeostasis and progressive degen-eration and increases the risk of cell death. Moderating the accrual of these defunctcomponents is likely a key in the promotion of longevity. While exercise is knownto promote healthy aging and mitigate age‐related pathologies, the molecular under-pinnings of this phenomenon remain largely unclear. However, recent evidencessuggest that exercise modulates the proteome. Similarly, caloric restriction (CR), aknown promoter of lifespan, is understood to augment intracellular protein quality.Autophagy is an evolutionary conserved recycling pathway responsible for thedegradation, then turnover of cellular proteins and organelles. This housekeepingsystem has been reliably linked to the aging process. Moreover, autophagic activitydeclines during aging. The target of rapamycin complex 1 (TORC1), a central kinaseinvolved in protein translation, is a negative regulator of autophagy, and inhibitionof TORC1 enhances lifespan. Inhibition of TORC1 may reduce the production ofcellular proteins which may otherwise contribute to the deleterious accumulationobserved in aging. TORC1 may also exert its effects in an autophagy‐dependentmanner. Exercise and CR result in a concomitant downregulation of TORC1 activityand upregulation of autophagy in a number of tissues. Moreover, exercise‐inducedTORC1 and autophagy signaling share common pathways with that of CR. There-fore, the longevity effects of exercise and CR may stem from the maintenance ofthe proteome by balancing the synthesis and recycling of intracellular proteins andthus may represent practical means to promote longevity

The Effect of Quercetin on Bone Turnover Markers, Inflammatory Markers, and Bone Mineral Density in Postmenopausal Women: A Double-Blind Placebo-Controlled Investigation

Maintaining optimal bone health prevents major bone disorders (e.g., osteoporosis) and prolongs longevity. Quercetin is a plant-based flavonoid that is suggested to have anti-inflammatory effects and may improve bone health. PURPOSE: To investigate the effects of quercetin supplementation over 90-days on prominent bone turnover markers (BTMs), inflammatory markers, bone mineral density (BMD), body composition, and physical functioning in postmenopausal women. METHODS: Thirty-three healthy, nonosteoporotic, postmenopausal women (59.2±7.0 years) participated in a double-blind, placebo-controlled investigation. Participants were randomized into one of two supplement groups: 1) 500 mg of quercetin (QUE) once daily or 2) 500 mg of methylcellulose (placebo; PLB) once daily. Pre- and post-testing visits included assessments of BTMs (i.e., osteocalcin [OC], procollagen type-I N-terminal propeptide [PINP], and type-I collagen cross-linked C-terminal telopeptide [CTX]), inflammatory markers (i.e., interleukin [IL]-6, tumor necrosis factor-alpha [TNF-a], and C-reactive protein [CRP]), BMD measurements, body composition measurements (i.e., body fat percentage), and physical function. RESULTS: The QUE group increased OC (p=0.016; d=0.89), PINP (p=0.030; d=0.64), and CTX (p=0.023; d=0.91) levels and decreased IL-6 (p=0.045; d=0.73) and TNF-a (p=0.021; d=0.90) levels compared to PLB. CRP (p=0.448; d=0.34), BMD, body composition, and physical function remained unchanged. CONCLUSION: The results indicate that QUE may maintain optimal bone health by mediating bone formation and decreasing pro-inflammatory cytokines

New Multisite Bioelectrical Impedance Device Compared to Hydrostatic Weighing and Skinfold Body Fat Methods

International Journal of Exercise Science 13(4): 1718-1728, 2020. The purpose of this study was to compare the Skulpt Chisel™ to seven-site skinfold (SKF) and hydrostatic weighing (HW) body fat percentage (%BF) estimates. Twenty-six participants (aged 24 ± 4 years; BMI 23.1 ± 3.5 kg∙m-2) were assessed. Significant differences in %BF estimates were found for all methodological pairings; p \u3c 0.05. The SKF method underestimated %BF compared to HW (-2.52 ± 3.42 %BF). The Skulpt Chisel™ overestimated %BF compared to both HW (3.38 ± 6.10 %BF) and SKF (5.90 ± 5.26 %BF). Limits of agreement comparing HW to Skulpt Chisel™ indicated a difference between 95% confidence interval bounds (Upper bound: 5.84 %BF, Lower bound 0.92 %BF) and for HW to SKF (Upper bound: -1.14 %BF, Lower bound: -3.91 %BF). Regression analysis showed no significant bias for any methodological pairing; (p \u3e 0.05). In conclusion, the Skulpt Chisel™ method should be used with caution when evaluating %BF of adults with similar demographics reported in this study

Effect of Novel Dietary Supplement on Metabolism in \u3cem\u3evitro\u3c/em\u3e and \u3cem\u3ein vivo\u3c/em\u3e

Obesity is an increasingly prevalent and preventable morbidity with multiple behavioral, surgical and pharmacological interventions currently available. Commercial dietary supplements are often advertised to stimulate metabolism and cause rapid weight and/or fat loss, although few well-controlled studies have demonstrated such effects. We describe a commercially available dietary supplement (purportedly containing caffeine, catechins, and other metabolic stimulators) on resting metabolic rate in humans, and on metabolism, mitochondrial content, and related gene expression in vitro. Human males ingested either a placebo or commercially available supplement (RF) in a randomized double-blind placebo-controlled cross-over fashion. Metabolic rate, respiratory exchange ratio, and blood pressure were measured hourly for 3 h post-ingestion. To investigate molecular effects, human rhabdomyosarcoma cells (RD) and mouse myocytes (C2C12) were treated with various doses of RF for various durations. RF enhanced energy expenditure and systolic blood pressure in human males without altering substrate utilization. In myocytes, RF enhanced metabolism, metabolic gene expression, and mitochondrial content suggesting RF may target common energetic pathways which control mitochondrial biogenesis. RF appears to increase metabolism immediately following ingestion, although it is unclear if RF provides benefits beyond those provided by caffeine alone. Additional research is needed to examine safety and efficacy for human weight loss

Mind-body Practices for Posttraumatic Stress Disorder

Abstract Background-Mind-body practices are increasingly used to provide stress reduction for posttraumatic stress disorder (PTSD). Mind-body practice encompasses activities with the intent to use the mind to impact physical functioning and improve health

Effect of Branched-Chain Amino Acid Supplementation on Recovery Following Acute Eccentric Exercise

This study investigated the effect of branched-chain amino acid (BCAA) supplementation on recovery from eccentric exercise. Twenty males ingested either a BCAA supplement or placebo (PLCB) prior to and following eccentric exercise. Creatine kinase (CK), vertical jump (VJ), maximal voluntary isometric contraction (MVIC), jump squat (JS) and perceived soreness were assessed. No significant (p \u3e 0.05) group by time interaction effects were observed for CK, soreness, MVIC, VJ, or JS. CK concentrations were elevated above baseline (p \u3c 0.001) in both groups at 4, 24, 48 and 72 hr, while CK was lower (p = 0.02) in the BCAA group at 48 hr compared to PLCB. Soreness increased significantly from baseline (p \u3c 0.01) in both groups at all time-points; however, BCAA supplemented individuals reported less soreness (p \u3c 0.01) at the 48 and 72 hr time-points. MVIC force output returned to baseline levels (p \u3e 0.05) at 24, 48 and 72 hr for BCAA individuals. No significant difference between groups (p \u3e 0.05) was detected for VJ or JS. BCAA supplementation may mitigate muscle soreness following muscle-damaging exercise. However, when consumed with a diet consisting of ~1.2 g/kg/day protein, the attenuation of muscular performance decrements or corresponding plasma CK levels are likely negligible

Reply to “Programming may matter most.” Response to “Metabolic effects of two high-intensity circuit training protocols: Does sequence matter?”

We appreciate the interest that our study elicited and the comments from a reader. We commend the reader of our paper for critically evaluating the protocol and results of the study. Here, we would like to respond to the statement made in the letter. Indeed, the rest intervals were longer and time at VO2max was lower in our study than recommended by Bucheit and Larsen.1 However, because the reader is interested in the practical implications of our study, we ask that they consider the following

Effects of high-intensity interval training while using a breathing-restrictive mask compared to intermittent hypobaric hypoxia

Background: Previous studies of the Elevation Training Mask (ETM) describe comparisons between groups using the ETM and controls for effects on aerobic performance. However, comparisons have not been made to intermittent hypoxic training (IHT). Further, how the ETM impacts exercise economy is unknown. Therefore, we sought to determine the effects of training with the ETM compared to IHT on aerobic performance and cycling economy. Methods: Thirty participants were randomized into an ETM, IHT, or control group (n = 10 each). Pre- and post-testing occurred using a ramp VO2max test on a cycle ergometer allowing submaximal power output (PO) measures of economy. Economy was measured using POs of 100, 125, and 150W. High-intensity cycling interval training (HIIT) occurred 2x/week for 30 min/session for six weeks. Sessions were 20 min of HIIT (30s at 100% peak power output (PPO) of pre VO2max, 90s active recovery at 25W, 10 bouts) with a 5-minute warm-up and cool-down. Repeated measures ANOVA was used for statistical analyses. RESULTS: All participants improved VO2max, PPO, and PO at ventilatory threshold 2 pre- to post-training (p < 0.05). Interactions between groups showed that the RER for the IHT group increased at 100W and 125W, and decreased at RERmax pre- to post-training while the ETM group showed the opposite response (p < 0.05). Conclusion: The ETM and IHT groups performed similarly to the control at maximal and submaximal effort following six weeks of training. The IHT group, but not the ETM group, experienced an increased glycolytic energy shift during submaximal exercise.This project was funded by the University of the New Mexico Graduate and Professional Student Association grants

Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo

Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201