Hamstring and knee injuries are associated with isometric hip and trunk muscle strength in elite Australian Rules and Rugby League players.

OBJECTIVES: This study investigated relationships between isometric trunk and hip extensor strength, lumbar muscle morphology, and the risk of hamstring and knee ligament injuries in Australian Football League and National Rugby League players. DESIGN: Prospective cohort study. METHODS: Trunk and hip extensor strength, multifidus and quadratus lumborum cross-sectional area were measured during the 2020 pre-season. Logistic regressions and decision trees were employed to explore associations between maximum strength, strength endurance, multifidus and quadratus lumborum cross-sectional area, age, previous injuries, and hamstring and knee ligament injury risk. RESULTS: Greater strength endurance [odds ratio = 0.42 (0.23-0.74), p = 0.004] and maximum strength [odds ratio = 0.55 (0.31-0.94), p = 0.039] reduced hamstring injury risk. Increased risk of knee ligament injuries was associated with larger multifidus [odds ratio = 1.66 (1.14-2.45), p = 0.008] and higher multifidus to quadratus lumborum ratio (odds ratio = 1.57 (1.13-2.23), p = 0.008]. Decision tree models indicated that low strength endurance (< 99 Nm) characterised hamstring strains, while high (≥ 1.33) multifidus to quadratus lumborum ratio mitigated risk. Knee ligament injuries were associated with larger (≥ 8.49 cm2) multifidus, greater (≥ 1.25) multifidus to quadratus lumborum ratio, and lower maximum strength (< 9.24 N/kg). CONCLUSIONS: Players with lower trunk and hip extensor maximum strength and strength endurance had increased risk of hamstring injuries, while knee ligament injury risk was elevated with larger multifidus cross-sectional area, higher multifidus to quadratus lumborum ratio, and lower maximum trunk and hip extensor strength.

High-Intensity Small Muscle Mass Training in Patients With Heart Failure: Rationale and Design of a Randomized Controlled Trial.

OBJECTIVE: Small muscle mass training localized to the quadriceps femoris muscle group has been proposed as an intervention to reverse heart failure-related skeletal muscle impairments. Although this training paradigm has demonstrated efficacy in heart failure, it remains to be evaluated in a conventional clinical context. Hence, the aim of this proposed study is to determine the effects of integrating high-intensity small muscle mass training (HISMT) isolated to the knee extensor muscles within a standard heart failure rehabilitation program. METHODS: This single-blind, randomized controlled trial will aim to recruit 70 participants with heart failure. Participants will be randomized to either (1) standard training: combination of upper and lower extremity cardiovascular and resistance-based exercises, or (2) HISMT plus modified standard training: bilateral knee extensor HISMT and a modified version of the standard training, so that the total volume of work will be similar to standard training alone. The training interventions will be undertaken twice weekly for 12 weeks in an outpatient clinical setting. Outcome measurements will be performed at baseline and after the 12-week intervention period. The primary outcome will be exercise capacity (6-Minute Walk Test), with secondary outcomes being physical performance measures, muscle strength, and health-related quality of life. Data will be analyzed using the intention-to-treat principle. IMPACT: This study will address a gap in the literature regarding the efficacy of small muscle training under routine clinical conditions for individuals with heart failure. The findings will also provide insight into the effects of HISMT within a heart failure rehabilitation program, thus enabling the optimization of exercise prescription for this patient population.

Where Does Blood Flow Restriction Fit in the Toolbox of Athletic Development? A Narrative Review of the Proposed Mechanisms and Potential Applications.

Blood flow-restricted exercise is currently used as a low-intensity time-efficient approach to reap many of the benefits of typical high-intensity training. Evidence continues to lend support to the notion that even highly trained individuals, such as athletes, still benefit from this mode of training. Both resistance and endurance exercise may be combined with blood flow restriction to provide a spectrum of adaptations in skeletal muscle, spanning from myofibrillar to mitochondrial adjustments. Such diverse adaptations would benefit both muscular strength and endurance qualities concurrently, which are demanded in athletic performance, most notably in team sports. Moreover, recent work indicates that when traditional high-load resistance training is supplemented with low-load, blood flow-restricted exercise, either in the same session or as a separate training block in a periodised programme, a synergistic and complementary effect on training adaptations may occur. Transient reductions in mechanical loading of tissues afforded by low-load, blood flow-restricted exercise may also serve a purpose during de-loading, tapering or rehabilitation of musculoskeletal injury. This narrative review aims to expand on the current scientific and practical understanding of how blood flow restriction methods may be applied by coaches and practitioners to enhance current athletic development models.

Cold water immersion in recovery following a single bout resistance exercise suppresses mechanisms of miRNA nuclear export and maturation.

Cold water immersion (CWI) following intense exercise is a common athletic recovery practice. However, CWI impacts muscle adaptations to exercise training, with attenuated muscle hypertrophy and increased angiogenesis. Tissue temperature modulates the abundance of specific miRNA species and thus CWI may affect muscle adaptations via modulating miRNA expression following a bout of exercise. The current study focused on the regulatory mechanisms involved in cleavage and nuclear export of mature miRNA, including DROSHA, EXPORTIN-5, and DICER. Muscle biopsies were obtained from the vastus lateralis of young males (n = 9) at rest and at 2, 4, and 48 h of recovery from an acute bout of resistance exercise, followed by either 10 min of active recovery (ACT) at ambient temperature or CWI at 10°C. The abundance of key miRNA species in the regulation of intracellular anabolic signaling (miR-1 and miR-133a) and angiogenesis (miR-15a and miR-126) were measured, along with several gene targets implicated in satellite cell dynamics (NCAM and PAX7) and angiogenesis (VEGF and SPRED-1). When compared to ACT, CWI suppressed mRNA expression of DROSHA (24 h p = 0.025 and 48 h p = 0.017), EXPORTIN-5 (24 h p = 0.008), and DICER (24 h p = 0.0034). Of the analyzed miRNA species, miR-133a (24 h p < 0.001 and 48 h p = 0.007) and miR-126 (24 h p < 0.001 and 48 h p < 0.001) remained elevated at 24 h post-exercise in the CWI trial only. Potential gene targets of these miRNA, however, did not differ between trials. CWI may therefore impact miRNA abundance in skeletal muscle, although the precise physiological relevance needs further investigation.

Efficacy of two doses of external counterpulsation (ECP) on glycemic control in people with type 2 diabetes mellitus: A randomized SHAM-controlled trial.

AIMS: To determine the efficacy of two doses of external counterpulsation (ECP) on glycemic control in people with type 2 diabetes mellitus (T2D), and any persistent benefits 7 weeks following treatment. METHODS: 50 participants with T2D were randomly assigned to either 1) 20x45-minute ECP sessions over 7 weeks (ECP45), 2) 20x30-minute ECP sessions over 7 weeks (ECP30) or 3) SHAM control. Outcomes were assessed at baseline, after 7 weeks of the intervention and 7 weeks after the interventions finished. Efficacy was determined from changes in HbA1c. RESULTS: After 7 weeks, there were significant between-group differences, with ECP45 lowering HbA1c compared to SHAM (mean [95% CI] -0.7 [-0.1 to -1.3] %; -7 [-1 to -15] mmol/mol). Within group changes were; ECP45 (mean ± SD -0.8 ± 0.8%; -8 ± 8 mmol/mol), ECP30 (-0.2 ± 0.5%; -2 ± 6 mmol/mol) and SHAM (-0.1 ± 0.9%; -1 ± 10 mmol/mol). HbA1c in the ECP45 group remained lower 7 weeks after completing the intervention; ECP45 (7.0 ± 1.1%; 53 ± 26 mmol/mol), ECP30 (7.7 ± 1.4%; 60 ± 16 mmol/mol) and SHAM (7.7 ± 1.0%; 60 ± 10 mmol/mol). CONCLUSIONS: In people with T2D, ECP45 for 7 weeks improved glycemic control when compared to ECP30 and a SHAM control group.

Duplicated zebrafish (Danio rerio) inositol phosphatases inpp5ka and inpp5kb diverged in expression pattern and function.

One hurdle in the development of zebrafish models of human disease is the presence of multiple zebrafish orthologs resulting from whole genome duplication in teleosts. Mutations in inositol polyphosphate 5-phosphatase K (INPP5K) lead to a syndrome characterized by variable presentation of intellectual disability, brain abnormalities, cataracts, muscle disease, and short stature. INPP5K is a phosphatase acting at position 5 of phosphoinositides to control their homeostasis and is involved in insulin signaling, cytoskeletal regulation, and protein trafficking. Previously, our group and others have replicated the human phenotypes in zebrafish knockdown models by targeting both INPP5K orthologs inpp5ka and inpp5kb. Here, we show that inpp5ka is the more closely related orthologue to human INPP5K. While both inpp5ka and inpp5kb mRNA expression levels follow a similar trend in the developing head, eyes, and tail, inpp5ka is much more abundantly expressed in these tissues than inpp5kb. In situ hybridization revealed a similar trend, also showing unique localization of inpp5kb in the pineal gland and retina indicating different transcriptional regulation. We also found that inpp5kb has lost its catalytic activity against its preferred substrate, PtdIns(4,5)P2. Since most human mutations are missense changes disrupting phosphatase activity, we propose that loss of inpp5ka alone can be targeted to recapitulate the human presentation. In addition, we show that the function of inpp5kb has diverged from inpp5ka and may play a novel role in the zebrafish.

Blood oxidative stress biomarkers in women: influence of oral contraception, exercise, and N-acetylcysteine.

PURPOSE: To compare physiological responses to submaximal cycling and sprint cycling performance in women using oral contraceptives (WomenOC) and naturally cycling women (WomenNC) and to determine whether N-acetylcysteine (NAC) supplementation mediates these responses. METHODS: Twenty recreationally trained women completed five exercise trials (i.e., an incremental cycling test, a familiarisation trial, a baseline performance trial and two double-blind crossover intervention trials). During the intervention trials participants supplemented with NAC or a placebo 1 h before exercise. Cardiopulmonary parameters and blood biochemistry were assessed during 40 min of fixed-intensity cycling at 105% of gas-exchange threshold and after 1-km cycling time-trial. RESULTS: WomenOC had higher ventilation (ß [95% CI] = 0.07 L·min-1 [0.01, 0.14]), malondialdehydes (ß = 12.00 mmol·L-1 [6.82, 17.17]) and C-reactive protein (1.53 mg·L-1 [0.76, 2.30]), whereas glutathione peroxidase was lower (ß =  22.62 mU·mL-1 [- 41.32, - 3.91]) compared to WomenNC during fixed-intensity cycling. Plasma thiols were higher at all timepoints after NAC ingestion compared to placebo, irrespective of group (all p < 0.001; d = 1.45 to 2.34). For WomenNC but not WomenOC, the exercise-induced increase in malondialdehyde observed in the placebo trial was blunted after NAC ingestion, with lower values at 40 min (p = 0.018; d = 0.73). NAC did not affect cycling time-trial performance. CONCLUSIONS: Blood biomarkers relating to oxidative stress and inflammation are elevated in WomenOC during exercise. There may be an increased strain on the endogenous antioxidant system during exercise, since NAC supplementation in WomenOC did not dampen the exercise-induced increase in malondialdehyde. Future investigations should explore the impact of elevated oxidative stress on exercise adaptations or recovery from exercise in WomenOC.

Effects of Acute Sleep Loss on Physical Performance: A Systematic and Meta-Analytical Review.

BACKGROUND: Sleep loss may influence subsequent physical performance. Quantifying the impact of sleep loss on physical performance is critical for individuals involved in athletic pursuits. DESIGN: Systematic review and meta-analysis. SEARCH AND INCLUSION: Studies were identified via the Web of Science, Scopus, and PsycINFO online databases. Investigations measuring exercise performance under 'control' (i.e., normal sleep, > 6 h in any 24 h period) and 'intervention' (i.e., sleep loss, ≤ 6 h sleep in any 24 h period) conditions were included. Performance tasks were classified into different exercise categories (anaerobic power, speed/power endurance, high-intensity interval exercise (HIIE), strength, endurance, strength-endurance, and skill). Multi-level random-effects meta-analyses and meta-regression analyses were conducted, including subgroup analyses to explore the influence of sleep-loss protocol (e.g., deprivation, restriction, early [delayed sleep onset] and late restriction [earlier than normal waking]), time of day the exercise task was performed (AM vs. PM) and body limb strength (upper vs. lower body). RESULTS: Overall, 227 outcome measures (anaerobic power: n = 58; speed/power endurance: n = 32; HIIE: n = 27; strength: n = 66; endurance: n = 22; strength-endurance: n = 9; skill: n = 13) derived from 69 publications were included. Results indicated a negative impact of sleep loss on the percentage change (%Δ) in exercise performance (n = 959 [89%] male; mean %Δ = - 7.56%, 95% CI - 11.9 to - 3.13, p = 0.001, I2 = 98.1%). Effects were significant for all exercise categories. Subgroup analyses indicated that the pattern of sleep loss (i.e., deprivation, early and late restriction) preceding exercise is an important factor, with consistent negative effects only observed with deprivation and late-restriction protocols. A significant positive relationship was observed between time awake prior to the exercise task and %Δ in performance for both deprivation and late-restriction protocols (~ 0.4% decrease for every hour awake prior to exercise). The negative effects of sleep loss on different exercise tasks performed in the PM were consistent, while tasks performed in the AM were largely unaffected. CONCLUSIONS: Sleep loss appears to have a negative impact on exercise performance. If sleep loss is anticipated and unavoidable, individuals should avoid situations that lead to experiencing deprivation or late restriction, and prioritise morning exercise in an effort to maintain performance.

Predicting Noncontact Lower Limb Injury Using Lumbar Morphology in Professional Australian Football and Rugby League Players.

INTRODUCTION: Noncontact lower limb injuries are common within the Australian Football League (AFL) and National Rugby League (NRL). Smaller (<8.5 cm2) lumbar multifidus at the fifth vertebra (LM L5) and larger (>8.2 cm2) quadratus lumborum (QL) cross-sectional area (CSA) have been associated with increased noncontact lower limb injury risk in AFL players. These associations have not been explored in an NRL cohort. This study will attempt to replicate previous research findings by confirming that muscle morphology is associated with noncontact lower limb injury. METHODS: AFL (n = 87) and NRL (n = 151) players underwent LM L2-L5 and QL CSA ultrasound measures during preseason. Each club's medical staff reported all noncontact lower limb injuries sustained in the subsequent regular season. LM and QL CSA, age, body mass index, and noncontact lower limb injuries were analyzed using multivariable logistic regression. RESULTS: Seventy-two players sustained a noncontact lower limb injury in the 2020 regular season (AFL = 21, NRL = 51). The multivariable logistic regression (odds ratio (OR) = 1.36; 95% confidence interval (CI), 1.02-1.85; P = 0.038) identified AFL players with larger QL CSA at increased risk of sustaining a noncontact lower limb injury during the regular season, but no relationship was found for LM CSA and noncontact lower limb injuries in the AFL (OR = 1.01; 95% CI, 0.36-2.78; P = 0.591) or NRL (OR = 0.63; 95% CI, 0.29-1.33; P = 0.149). CONCLUSIONS: AFL players who sustained regular season noncontact lower limb injuries had larger QL CSA in preseason tests. No significant associations between either LM L5 CSA or LM L5 to QL ratio and regular season noncontact lower limb injuries were found.

Acute cellular and molecular responses and chronic adaptations to low-load blood flow restriction and high-load resistance exercise in trained individuals.

Blood flow restriction (BFR) with low-load resistance exercise (RE) is often used as a surrogate to traditional high-load RE to stimulate muscular adaptations, such as hypertrophy and strength. However, it is not clear whether such adaptations are achieved through similar cellular and molecular processes. We compared changes in muscle function, morphology, and signaling pathways between these differing training protocols. Twenty-one males and females (means ± SD: 24.3 ± 3.1 yr) experienced with resistance training (4.9 ± 2.6 yr) performed 9 wk of resistance training (three times per week) with either high-loads (75%-80% 1RM; HL-RT), or low-loads with BFR (30%-40% 1RM; LL-BFR). Before and after the training intervention, resting muscle biopsies were collected, and quadricep cross-sectional area (CSA), muscular strength, and power were measured. Approximately 5 days following the intervention, the same individuals performed an additional "acute" exercise session under the same conditions, and serial muscle biopsies were collected to assess hypertrophic- and ribosomal-based signaling stimuli. Quadricep CSA increased with both LL-BFR (7.4 ± 4.3%) and HL-RT (4.6 ± 2.9%), with no significant differences between training groups (P = 0.37). Muscular strength also increased in both training groups, but with superior gains in squat 1RM occurring with HL-RT (P < 0.01). Acute phosphorylation of several key proteins involved in hypertrophy signaling pathways, and expression of ribosomal RNA transcription factors occurred to a similar degree with LL-BFR and HL-RT (all P > 0.05 for between-group comparisons). Together, these findings validate low-load resistance training with continuous BFR as an effective alternative to traditional high-load resistance training for increasing muscle hypertrophy in trained individuals.NEW & NOTEWORTHY Low-load resistance exercise with blood flow restriction (LL-BFR) is an effective method for stimulating muscular adaptations, but phenotypical and mechanistic comparisons with traditional high-load training (HL-RT) in trained populations are scarce. The findings indicate that hypertrophy, but not strength, is comparable between LL-BFR and HL-RT, and the acute cellular and molecular processes for hypertrophy were similar, but not identical, between protocols. Thus, LL-BFR is an effective alternative to HL-RT for obtaining hypertrophy in trained populations.

Temporal changes in blood oxidative stress biomarkers across the menstrual cycle and with oral contraceptive use in active women.

PURPOSE: To examine the temporal changes in blood oxidative stress biomarkers in recreationally-trained women that were naturally-cycling (WomenNC) or using oral contraceptives (WomenOC) across one month. METHODS: Blood samples were acquired at three timepoints of the menstrual cycle (1: early-follicular, 2: late-follicular and 3: mid-luteal) and oral contraceptive packet (1: InactiveOC, 2: Mid-activeOC and 3: Late-activeOC) for determination of estradiol, progesterone, oxidative stress, C-reactive protein (CRP) and other cardiometabolic biomarkers in plasma and serum. RESULTS: There was a Group by Time effect on estradiol (p < 0.001, partial η2 = 0.64) and progesterone (p < 0.001, partial η2 = 0.77). Malondialdehyde, lipid hydroperoxides and CRP concentrations were higher in WomenOC during Late-activeOC compared to InactiveOC (+ 96%, + 23% and + 104%, respectively, p < 0.05). However, there were no changes in these biomarkers across the menstrual cycle in WomenNC (p > 0.05). At all timepoints (i.e., 1, 2 and 3), WomenOC had elevated lipid hydroperoxides (+ 28, + 48% and + 50%) and CRP (+ 71%, + 117% and + 130%) compared to WomenNC (p < 0.05, partial η2 > 0.25). There was no Group by Time effect on non-enzymatic antioxidants or glutathione peroxidase; however, glutathione peroxidase was lower in WomenOC, i.e., main effect of group (p < 0.05, partial η2 > 0.20). CONCLUSION: These findings demonstrate that WomenOC not only have higher oxidative stress and CRP than WomenNC, but also a transient increase across one month of habitual oral contraceptive use. Since changes in oxidative stress and CRP often relate to training stress and recovery, these outcomes may have implications to workload monitoring practices in female athletes.

Similar Morphological and Functional Training Adaptations Occur Between Continuous and Intermittent Blood Flow Restriction.

ABSTRACT: Davids, CJ, Raastad, T, James, L, Gajanand, T, Smith, E, Connick, M, McGorm, H, Keating, S, Coombes, JS, Peake, JM, and Roberts, LA. Similar morphological and functional training adaptations occur between continuous and intermittent blood flow restriction. J Strength Cond Res 35(7): 1784-1793, 2021-The aim of the study was to compare skeletal muscle morphological and functional outcomes after low-load resistance training using 2 differing blood flow restriction (BFR) protocols. Recreationally active men and women (n = 42 [f = 21], 24.4 ± 4.4 years) completed 21 sessions over 7 weeks of load-matched and volume-matched low-load resistance training (30% 1 repetition maximum [1RM]) with either (a) no BFR (CON), (b) continuous BFR (BFR-C, 60% arterial occlusion pressure [AOP]), or (c) intermittent BFR (BFR-I, 60% AOP). Muscle mass was assessed using peripheral quantitative computed tomography before and after training. Muscular strength, endurance, and power were determined before and after training by assessing isokinetic dynamometry, 1RM, and jump performance. Ratings of pain and effort were taken in the first and final training session. An alpha level of p < 0.05 was used to determine significance. There were no between-group differences for any of the morphological or functional variables. The muscle cross sectional area (CSA) increased pre-post training (p = 0.009; CON: 1.6%, BFR-C: 1.1%, BFR-I: 2.2%). Maximal isometric strength increased pre-post training (p < 0.001; CON: 9.6%, BFR-C: 14.3%, BFR-I: 19.3%). Total work performed during an isokinetic endurance task increased pre-post training (p < 0.001, CON: 3.6%, BFR-C: 9.6%, BFR-I: 11.3%). Perceptions of pain (p = 0.026) and effort (p = 0.033) during exercise were higher with BFR-C; however, these reduced with training (p = 0.005-0.034). Overall, these data suggest that when 30% 1RM loads are used with a frequency of 3 times per week, the addition of BFR does not confer superior morphological or functional adaptations in recreationally active individuals. Furthermore, the additional metabolic stress that is proposed to occur with a continuous BFR protocol does not seem to translate into proportionally greater training adaptations. The current findings promote the use of both intermittent BFR and low-load resistance training without BFR as suitable alternative training methods to continuous BFR. These approaches may be practically applicable for those less tolerable to pain and discomfort associated with ischemia during exercise.

Anti-Inflammatory and Antioxidant Effects of Dietary Supplementation and Lifestyle Factors.

Trends relating to specific diets and lifestyle factors like physical (in) activity have formed in recent times [...].

Reliability of a point-of-care device to determine oxidative stress in whole blood before and after acute exercise: A practical approach for the applied sports sciences.

Measuring alterations in redox homoeostasis in athletes can provide insights into their responses to training such as adaptations or fatigued states. However, redox monitoring is impractical in athletes given the time burden of venepuncture and subsequent laboratory assays. The ability of point-of-care tests (POC): 1) Free Oxygen Radical Test (FORT) and 2) Free Oxygen Radical Defence (FORD), to reliably measure whole blood oxidative stress between days and after exercise is unknown as well as their relationship with laboratory measures (F2-isoprostanes, total antioxidant capacity; TAC). Participants completed two trials performed on separate days comprising blood sampling at rest (n=22) and after treadmill-running (n=14). Between-day CVs for FORT (4.6%) and FORD (4.8%) were acceptable at rest. There was no difference in the between-day magnitude of change in any biomarker from pre- to post-exercise (p>0.05), yet the within-trial change in FORD was variable (trial one: +4.5%, p=0.15; trial two: +6.3%, p<0.05). TAC and FORD were significantly correlated pre- and post-exercise (r=~0.53, p<0.05), whereas F2-isoprostanes and FORT had a significant correlation pre-exercise only (r=0.45, p=0.03). Overall, the POC tests are reliable and could be used for baseline longitudinal redox monitoring. More data is required on POC tests for assessing redox perturbations induced by exercise.

Altered skeletal muscle glucose-fatty acid flux in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis is characterized by the degeneration of upper and lower motor neurons, yet an increasing number of studies in both mouse models and patients with amyotrophic lateral sclerosis suggest that altered metabolic homeostasis is also a feature of disease. Pre-clinical and clinical studies have shown that modulation of energy balance can be beneficial in amyotrophic lateral sclerosis. However, the capacity to target specific metabolic pathways or mechanisms requires detailed understanding of metabolic dysregulation in amyotrophic lateral sclerosis. Here, using the superoxide dismutase 1, glycine to alanine substitution at amino acid 93 (SOD1G93A) mouse model of amyotrophic lateral sclerosis, we demonstrate that an increase in whole-body metabolism occurs at a time when glycolytic muscle exhibits an increased dependence on fatty acid oxidation. Using myotubes derived from muscle of amyotrophic lateral sclerosis patients, we also show that increased dependence on fatty acid oxidation is associated with increased whole-body energy expenditure. In the present study, increased fatty acid oxidation was associated with slower disease progression. However, within the patient cohort, there was considerable heterogeneity in whole-body metabolism and fuel oxidation profiles. Thus, future studies that decipher specific metabolic changes at an individual patient level are essential for the development of treatments that aim to target metabolic pathways in amyotrophic lateral sclerosis.

The Effects of Cold Water Immersion and Active Recovery on Molecular Factors That Regulate Growth and Remodeling of Skeletal Muscle After Resistance Exercise.

Regular postexercise cooling attenuates muscle hypertrophy, yet its effects on the key molecular factors that regulate muscle growth and remodeling are not well characterized. In the present study, nine men completed two sessions of single-leg resistance exercise on separate days. On 1 day, they sat in cold water (10°C) up to their waist for 10 min after exercise. On the other day, they exercised at a low intensity for 10 min after exercise. Muscle biopsies were collected from the exercised leg before, 2, 24, and 48 h after exercise in both trials. These muscle samples were analyzed to evaluate changes in genes and proteins involved in muscle growth and remodeling. Muscle-specific RING finger 1 mRNA increased at 2 h after both trials (P < 0.05), while insulin-like growth factor (IGF)-1 Ec, IGF-1 receptor, growth arrest and DNA damage-inducible protein 45, collagen type I alpha chain A, collagen type III alpha chain 1, laminin and tissue inhibitor of metallopeptidase 1 mRNA increased 24-48 h after both trials (P < 0.05). By contrast, atrogin-1 mRNA decreased at all time points after both trials (P < 0.05). Protein expression of tenascin C increased 2 h after the active recovery trial (P < 0.05), whereas FoxO3a protein expression decreased after both trials (P < 0.05). Myostatin mRNA and ubiquitin protein expression did not change after either trial. These responses were not significantly different between the trials. The present findings suggest that regular cold water immersion attenuates muscle hypertrophy independently of changes in factors that regulate myogenesis, proteolysis and extracellular matrix remodeling in muscle after exercise.

Organosulfur Compounds: A Review of Their Anti-inflammatory Effects in Human Health.

Phytonutrients are widely recognized for providing protective human health benefits. Among the phytonutrients, epidemiological and experimental studies show that dietary organosulfur compounds (OSC) play a significant role in preventing various human pathological progressions, including chronic inflammation, by decreasing inflammatory mediators such as nitric oxide (NO), prostaglandin (PG)E2, interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, and IL-17, which are all typical hallmarks of inflammation. Evidence supports OSC in reducing the expression of these markers, thereby attenuating chronic inflammatory processes. Nuclear factor-kappa B (NF-κB) is a key regulating factor during inflammation, and novel evidence shows that OSC downregulates this transcriptional factor, thus contributing to the anti-inflammatory response. In vitro and in vivo studies show that inflammation is mechanistically linked with acute and chronic pathological conditions including cancer, diabetes, obesity, neural dysfunction, etc. Furthermore, a considerable number of experiments have demonstrated that the anti-inflammatory properties of OSC occur in a dose-dependent manner. These experiments also highlight indirect mechanisms as well as potent co-functions for protective roles as antioxidants, and in providing chemoprotection and neuroprotection. In this brief review, we provided an overview of the anti-inflammatory effects of OSC and elucidated probable mechanisms that are associated with inflammation and chronic disorders.

Mobilizing serum factors and immune cells through exercise to counteract age-related changes in cancer risk.

An increasing body of evidence suggests that age-related immune changes and chronic inflammation contribute to cancer development. Recognizing that exercise has protective effects against cancer, promotes immune function, and beneficially modulates inflammation with ageing, this review outlines the current evidence indicating an emerging role for exercise immunology in preventing and treating cancer in older adults. A specific focus is on data suggesting that muscle- derived cytokines (myokines) mediate anti-cancer effects through promoting immunosurveillance against tumourigenesis or inhibiting cancer cell viability. Previous studies suggested that the exercise-induced release of myokines and other endocrine factors into the blood increases the capacity of blood serum to inhibit cancer cell growth in vitro. However, little is known about whether this effect is influenced by ageing. Prostate cancer is the second most common cancer in men. We therefore examined the effects of serum collected before and after exercise from healthy young and older men on the metabolic activity of androgen-responsive LNCaP and androgen-unresponsive PC3 prostate cancer cells. Exercise-conditioned serum collected from the young group did not alter cell metabolic activity, whereas post-exercise serum (compared with pre-exercise serum) from the older men inhibited the metabolic activity of LNCaP cancer cells. Serum levels of candidate cancer-inhibitory myokines oncostatin M and osteonectin increased in both age groups following exercise. Serum testosterone increased only in the younger men postexercise, potentially attenuating inhibitory effects of myokines on the LNCaP cell viability. The data from our study and the evidence in this review suggest that mobilizing serum factors and immune cells may be a key mechanism of how exercise counteracts cancer in the older population.