Pre Exercise Research Articles

Reliability of a wearable sweat rate monitor and routine sweat analysis techniques under heat stress in females

IntroductionThe aim of the study was to evaluate the reliability of five different sweat analysis techniques which measure; whole body sweat rate [WBSR], local sweat rate [LSR] (via technical absorbent [TA] method and KuduSmart® monitor), sweat conductivity [SC] and sweat gland activation [SGA] in a female population when exercising moderately under heat stress. MethodsFourteen females (age; 26 ± 7 years, body mass; 66.5 ± 7.6 kg, height; 167.1 ± 6.4 cm) completed a preliminary threshold walking test (to determine exercise intensity) and two main trials, separated by 2 days. Main trials consisted of 30-min seated rest in the environmental chamber (35 °C, 50% relative humidity) in an upper body sauna-suit, before its removal, and walking at a moderate intensity (4 metabolic equivalents) for 30-min (speeds ranged from 4.8 to 6.5 km h−1). WBSR was measured via nude mass pre and post exercise. The TA and Tegaderm patches (for sweat sodium chloride) were placed on the back, forearm and chest for the entire 60-min, replicated for all participants for both trials. SGA was assessed following the 60-min trial and the KuduSmart® monitor was placed on the left arm for the 30-min of exercise. ResultsWBSR, LSR methods and SC demonstrated no difference between trials (p > 0.05), good agreement (within limits), strong correlations (r ≥ 0.88) and low typical error of measurements [TEM] (< 0.04 L min−1, 0.13 mg min−1 cm−2 and 8 mmol L−1, respectively). SGA method showed moderate intra-class correlation (r = 0.80), with high TEM (5 glands) and large limits of agreement. ConclusionSudomotor function is reliable, as demonstrated by good reliability, small TEM and strong correlations. The use of these sweat techniques is appropriate and practical in females who are exercising at moderate intensity under heat stress, and so, may aid future interventions. SGA shows larger variation and should be used with caution.

MESA 2: DIABETES MELLITUS TIPO 1 Y ACTIVIDAD FÍSICA

En personas con diabetes tipo 1 (DM1) el ejercicio físico realizado en forma regular brindaría protección cardiovascular y tendría propiedades inmunomoduladoras pero la compleja interacción entre los efectos del ejercicio sobre el metabolismo glucídico y la terapia con insulina exógena supone un verdadero desafío. El ejercicio aeróbico por la contracción muscular disminuye la glucemia, conduce a un estado de hiperinsulinemia relativa y genera hipoglucemia al inicio o después del mismo mientras que el ejercicio anaeróbico se asocia a hiperglucemia por aumento de catecolaminas e incremento de lactato que favorece la neoglucogénesis hepática. El deterioro de la respuesta de hormonas contrarreguladoras existente en la DM1 amplifica la variabilidad glucémica y dificulta el control metabólico.Existen guías y recomendaciones que buscan brindar un marco de seguridad para la prescripción de actividad física considerando la multiplicidad de disciplinas deportivas, la edad del paciente y la evaluación de las complicaciones crónicas de la diabetes antes del inicio de la misma. Entre las estrategias terapéuticas se encuentran la modulación con hidratos de carbono, la adecuación pre y pos ejercicio de la insulinoterapia y el control intensivo de glucemia y cetonas. Los nuevos infusores de insulina y monitoreo glucémico ofrecen la posibilidad del fraccionamiento y/o suspensión de dosis convirtiéndose en el gold standard entre los deportistas de alto rendimiento. A futuro modelos integrados con calculadoras de ejercicio inteligentes, capacidad predictiva y de “aprendizaje individualizado” (páncreas artificial) posibilitarán mantener la euglucemia y optimizar los beneficios del ejercicio como parte del tratamiento.

The Acute Effects of Different Forms of Suspension Push-Ups on Oxygen Consumption, Salivary Testosterone and Cortisol and Isometric Strength.

Suspension exercise systems are being used in strength and conditioning facilities, fitness centers, rehabilitation centers and home gyms. Though some evidence exists regarding the impact of training with these systems, more work is needed for a better understanding. The purpose of the present investigation was to examine the acute effects of an exercise session with 2 (hands only) and 4 straps (hands and feet) in the push-up exercise compared to a work-matched bench press exercise session. The participants for this repeated measures, cross-over investigation were 18 healthy college-aged males (age: 24.8 ± 3.5 yrs, body mass: 81.8 ± 7.8 kg, body height: 178.9 ± 4.5 cm). The conditions were 6 sets of 10 repetitions of suspension push-ups using two straps (DUAL) for the hands, fours straps (QUAD) for hands and feet and a traditional bench press exercise matched to the average resistance during the suspension push-up. The participants performed all repetitions at a controlled cadence. Expired gases, and heart rate were monitored continuously during the exercise session. Pre and post exercise saliva samples were collected to quantify changes in testosterone and cortisol. Upper body isometric strength tests ( UBIST) were performed (Post, 1 hr, 24 hr, 48 hr) to evaluate changes in force production during recovery. Data analysis via repeated measures ANOVA revealed a significant trend for increased oxygen consumption in the QUAD condition compared to the bench press (p = 0.019). Additionally, both suspension conditions resulted in a reduced respiratory exchange ratio as compared to the bench press (p < 0.05). A significant main effect was noted for time in all conditions regarding isometric strength (p < 0.001), but no differences between conditions were revealed. Testosterone and cortisol responses did not differ between conditions. Based upon these data, it appears that when matched for work, suspension exercise results in equivalent reductions in muscle force, but greater oxygen consumption compared to isotonic exercise.

PL-019 Effect of early exercise on autophagy of liver tumor in mice

Objective To investigate whether the liver autophagy level can be altered by pre exercise training in mice liver tumors.&#x0D; Methods 40 Male C57BL/6J mice aged 7 months were randomly divided into 2 groups: control group (YC) and exercise group (YE). YE were exercised on a treadmill for 12 weeks (12m/min). After12 weeks each group was randomly divided into two groups. The tumor model was constructed by injection of HEPA1- 6 mouse hepatoma cell into liver tissue.Then the groups were control group (YC), exercise group (YE), tumor group (YCT), exercise tumor group (YET).The experimental samples were prepared on the 13 day after the tumor model was constructed. the hematoxylin and eosin stain of the liver was observed.The expression of autophagy related protein BECLIN1, LC3-II and ATG5 in liver tissues of mice was detected by Western blot.&#x0D; Results Compared with YCT group,the boundary of inflammatory cells and tumor cells in YET group was clear with normal cells.Compared with YCT group, the expression levels of BECLIN1, LC3-II and ATG5 in liver tissue of YET group were significantly higher (p &lt; 0.01, P &lt; 0.01, P &lt; 0.05).&#x0D; Conclusions Early exercise can help the 7 month old mice to resist the occurrence and development of the liver tumor. It's probably associated with increased level of autophagy in the liver by early exercise training.

8주간의 복합운동프로그램이 여성들의 신체조성, 체력, 프레밍햄 리스크 스코어 및 혈관상태에 미치는 영향

The purpose of this study was to investigate the effects of combined exercise on physical fitness level, framingham risk score and vascular elasticity on women. All participants performed physical fitness test and measurement of vascular elasticity between pre and post exercise intervention program. Cardiovascular disease risk factor was assessed using the framingham risk score. Wilcoxon signed-rank test or paired t-test were performed to confirm changes in each factors pre and post the exercise program. The results were following : Except the hand grip strength and muscle power, all physical fitness levels such as muscular endurance, cardiovascular endurance, flexibility, agility, muscle power were significantly increases between pre and post exercise program. Furthermore, significant differences were found in the framingham risk score and vascular elasticity wave type between pre and post exercise program. In conclusion, we suggest that the combined exercise program reduces the cardiovascular disease risk and improve vascular elasticity on women.

Effects of acute or chronic heat exposure, exercise and dehydration on plasma cortisol, IL-6 and CRP levels in trained males

This study examined the acute and chronic effects of euhydrated and hypohydrated heat exposure, on biomarkers of stress and inflammation. Eight trained males [mean (SD) age: 21 (3) y; mass: 77.30 (4.88) kg; V̇O2max: 56.9 (7.2) mL kg−1 min−1] undertook two heat acclimation programmes (balanced cross-over design), once drinking to maintain euhydration and once with restricted fluid-intake (permissive dehydration). Days 1, 6, and 11 were 60 min euhydrated exercise-heat stress tests (40 °C; 50% RH, 35% peak power output), days 2–5 and 7–10 were 90 min, isothermal-strain (target rectal temperature: 38.5 °C) exercise-heat sessions. Plasma was obtained pre- and post- exercise on day 1, 2, and 11 and analysed for cortisol, interleukin-6 (IL-6), and C-reactive protein (CRP). Cortisol and CRP were also assessed on day 6. IL-6 was elevated following the initial (acute) 90 min isothermal heat strain exercise-heat exposure (day 2) with permissive dehydration ((pre exercise: 1.0 pg mL−1 [0.9], post-exercise: 1.8 pg mL−1 [1.0], P = .032) and when euhydrated (pre-exercise: 1.0 pg mL−1 [1.4], post-exercise: 1.6 pg mL−1 [2.1], P = .048). Plasma cortisol levels were also elevated but only during permissive dehydration (P = .032). Body mass loss was strongly correlated with Δcortisol (r = −0.688, P = .003). Although there was a trend for post-exercise cortisol to be decreased following both heat acclimation programmes (chronic effects), there were no within or between intervention differences in IL-6 or CRP. In conclusion, acute exercise in the heat increased IL-6 and cortisol only when fluid-intake is restricted. There were no chronic effects of either intervention on biomarkers of inflammation as evidenced by IL-6 and CRP returning to basal level at the end of heat acclimation.

Moderately heavy exercise produces lower cardiovascular, RPE, and discomfort compared to lower load exercise with and without blood flow restriction.

To determine the acute cardiovascular and perceptual responses of low-load exercise with or without blood flow restriction and compare those responses to that of moderately heavy exercise. Twenty-two participants completed unilateral elbow flexion exercise with a moderately heavy-load- [70% one-repetition maximum (1RM); 70/0] and with three low-load conditions (15% 1RM) in combination with 0% (15/0), 40%, (15/40) and 80% (15/80) arterial occlusion pressure. Participants exercised until failure (or until 90 repetitions per set). The cardiovascular response (arterial occlusion) was measured pre and post exercise and the perceptual responses [ratings of perceived exertion (RPE) and discomfort] were determined before and after each set of exercise. For arterial occlusion pressure, the lower-load conditions had greater change from pre to post compared to 70/00 (e.g., 15/80: 44 vs. 70/0: 34mmHg). RPE was highest across the sets for the 15/80 condition with the other conditions having similar RPE (e.g., set 4: median rating of 17.2 for 15/80 vs. ~ 15.5 for other conditions). Ratings of discomfort were also greatest for the 15/80 condition (15/80 > 15/40 > 15/0 > 70/0). Exercise volume within the 15/0 and 15/40 conditions were similar but were significantly greater than that observed with the 15/80 and 70/0 conditions. Low-load exercise to volitional failure results in a greater cardiovascular response to that of moderately heavy-load exercise. When high pressure is applied to low load exercise, there is a reduction in exercise volume but an elevated perceptual response that may be an important consideration when applying this stimulus in practice.

Acute Exercise-Induced Response of Platelet-Monocyte Complexes in Obese Postmenopausal Women

Inactivity-related diseases such as cardiovascular disease (CVD) are linked to chronic low-grade, systemic inflammation. Platelet-monocyte complexes (PMCs) are markers of in vivo platelet activation and atherosclerosis, and may be early indicators of subclinical inflammation. PURPOSE: To examine the effects of a single exercise bout on PMCs in those at risk for CVD. METHODS: Twenty-five overweight-obese (BMI 32.7 ± 5.2 kg·m-2, 55-75 yr) women were randomly assigned to either the exercise (EX, n=13) or non-exercise control (CON, n=12) group. EX performed 2 sets of 8 resistance exercises and a 25-min treadmill walk at 70-80% HRR. Blood was obtained pre-exercise (PR), post- (PO), 1-hour and 2 hours post-exercise (1HR and 2HR). Blood was obtained at the same time points in CON. PMCs were identified via flow cytometry and analyzed in each monocyte phenotype. Monocyte phenotypes were defined as: Mon1 (CD14+CD16−CCR2+), Mon2 (CD14+CD16+CCR2+), and Mon3 (CD14+CD16+CCR2−). All events positive for both CD14 and CD42a (marker for platelets) were considered PMCs. RESULTS: A main effect for time revealed an increase in total PMC number at PO (p=0.036). This increase appears to have been driven by EX (EX = 61.5%; CON = 33.8% increase). Mon1 and Mon2 PMC responses were similar. A significant time x group interaction for Mon3 PMCs (p=0.002) indicated an increase from PR to PO (PR = 5218±1170 cells·ml-1, PO = 8195±1152 cells·ml-1), and a decrease from PO to 1HR and 2HR (1HR = 3767±820 cells·ml-1 2HR = 3818±814 cells·ml-1). PMC number remained constant for CON at all timepoints. Estimated VO2max was negatively correlated with CD42a MFI (a marker of platelet density per monocyte) (r = -0.583, p = 0.003). Systolic blood pressure (SBP) positively correlated with percent PMC (% CD42a positive monocytes; r = 0.458, p = 0.042). CONCLUSIONS: Aerobic fitness appears to reduce platelet activation indicated by the negative relationship between VO2max and CD42a MFI. Chronic elevations in resting SBP are linked to PMC percentage, possibly due to sheer stress-induced platelet activation. It is possible that PMC elevation at PO is at least partially driven by exercise- induced increases in BP. These results support previous literature, indicating that PMCs are a marker CVD risk and may elucidate one mechanism by which physical fitness reduces risk for CVD.

Exercise At Simulated Altitude Increases Gastrointestinal Barrier Damage And Promotes Leukocyte Activation

PURPOSE: This study tested whether altitude-associated ischemic stress damages the gastrointestinal barrier, activates leukocytes, and promotes inflammation. METHODS: Subjects (N = 5) completed two 60 min bouts of matched-workload treadmill exercise (65% VO2max). One under control conditions (Normoxia, FIO2 = 20.9%) and the other at ~4000 m of simulated altitude (Hypoxia, FIO2 = 13.5%). Pulse oximetry was used to measure peripheral oxygen saturation (SpO2) and near-infrared spectroscopy was used to measure absolute tissue saturation (StO2) at 5 min intervals throughout exercise. Fatty acid-binding protein (I-FABP), markers of leukocyte activation (CD14, ICAM-1, IL-8, MCP-1, MPO), and cytokines (TNFα, IL-1β, IL-6, IL-10, IL-12) were measured in plasma samples that were collected Pre, Post, 1hr-Post, and 4hr-Post exercise. Data were analyzed with 2-Way (Condition x Time) RM ANOVAs with significance set at p ≤ 0.05. Post hocs (Newman-Keuls) were run where appropriate. RESULTS: Significant reductions in SpO2 and StO2 were shown during exercise at simulated altitude [(SpO2: Hypoxia = 79 ± 1% vs Normoxia = 94 ± 0.5%, p = 0.03) (StO2: Hypoxia = 61 ± 2 vs Normoxia = 69 ± 2, p < 0.01)]. A significant interaction effect was shown for I-FABP (p = 0.05), with post hoc analysis indicating I-FABP increased more from Pre to Post in Hypoxia (112%) than in Normoxia (30%). IL-8 increased more from Pre to Post (60%) and 1hr-Post (83%) in Hypoxia than in Normoxia (33% & 57%, respectively). Significant main effects were also shown for IL-6, ICAM-1, CD14, and MCP-1. All were higher in Hypoxia (p ≤ 0.05). MPO increased at Post in Normoxia (121%, p = 0.05) but did not increase until 1hr-Post in Hypoxia (129%, p = 0.02). CONCLUSIONS: Preliminary data suggest exercise at altitude may increase gastrointestinal barrier damage and leukocyte activation, as indicated by higher levels of I-FABP, IL-8, and MCP-1. Increased CD14 and ICAM-1 suggest TLR4-mediated inflammatory signaling may also be elevated, but the delayed increase in MPO following exercise at altitude warrants further investigation.

No Lipolytic Suppression With Pre Exercise Carbohydrate Regardless of its Glycemic Index

No Lipolytic Suppression With Pre Exercise Carbohydrate Regardless of its Glycemic Index

Caffeine and Citrate Aurantium Supplementation Alter Resting Cardiac Autonomic Function but Not During Recovery

PURPOSE: To examine the combined effects of the pre exercise complex Citrate Aurantium and Caffeine (CA+C) on cardiac autonomic activity following ingestion and immediately after high-intensity anaerobic exercise in habitual caffeine users. METHODS: Ten physically active males (25.1± 3.9 years; mass 78.7± 9.5kg) who habitually consume caffeine (≥ 1 serving a day [95mg] 4 days a week) participated. This was a double-blind crossover design, where either a CA+C or a placebo capsule was consumed followed by a 45-min ingestion period, a repeated Wingate protocol, and a 45-min recovery period. Cardiac autonomic activity was assessed through Heart Rate (HR), plasma epinephrine (E) and norepinephrine (NE), and markers of Heart Rate Variability (HRV): root mean squared of successive R-R differences (RMSSD); Standard Deviation of R-R intervals (SDNN); High-Frequency (HF); Low-Frequency (LF); and its ratio (LF:HF). Markers were taken at four time points: pre-Ingestion (PRE-ig), 40-45-min post (Post- ig); Wingate recovery (PRE-rcv), 40-45-min post recovery (Post-rcv). RESULTS: Markers that violated normality were naturally log transformed prior to further analysis (ln). Pre-planned comparisons were performed to assess differences between pre and post time points as well as the corresponding time point of the other trial within their respected phase. During the CA+C trial, an increase in HR, lnSDNN, lnLF, EPI, and NE were observed at Post-ig when compared to Pre-ig (p≤0.05). Significant differences were observed in all markers, except LF:HF, during the CA+C and PLA trials from the Pre-rcv to Post-rcv (p≤0.05). CONCLUSION: The consumption of CA+C stimulates sympathetic activity during rest (e.g. ingestion phase) without influencing parasympathetic activity. CA+C provides no influence over cardiac autonomic recovery.

Effects of exercise on plasma lactic acid and body temperature in man, following a standardized meal

Background: The effects of exercise on plasma lactic acid level and body temperature following a standardized meal were carried out on 20 healthy young individuals (aged between 18 and 29 yrs.), consisting of 10 males and 10 females. The physical fitness of the subjects was determined measuring their blood pressure, pulse rate and other physical examinations.Methodology: Each subject was made to ride the bicycle ergometer for 6mins, at a rhythmic cadence of 50revolution/ min via 100beats metronome counts. Blood samples were collected before and after the exercise to analyze for the pre and post exercise plasma lactate levels. Pre and post-exercise values for body temperature were also measured. Statistical tests were carried out at 95% CI (P=0.05).Result: The result obtained showed that exercise causes a statistically significant increase (p&lt; 0.05) in both plasma lactate concentration (from a pre-exercise mean value of 0.98 ±0.07mmol/L to post- exercise mean value of 2.84 ±0.21mmol/L) and body temperature (from a mean value of 36.45 ±0.130C before exercise to a mean value of 36.91 ±0.190C after exercise).Conclusion: There was a statistically significant increase in plasma lactateand body temperature because of exposure to exercise which is in line with findings from most previous studies.Bangladesh Journal of Medical Science Vol.17(2) 2018 p.270-274

Abstract P031: Effect of Exercise on Function and Differentiation of Adipose Tissue Derived Mesenchymal Stromal Cells (MSCs)

Approximately 422 million people have diabetes worldwide (2014) and it is predicted that diabetes will rise by nearly 54% by 2030. Aerobic exercise is known to show positive effect on health of diabetic and pre diabetic patients. The effect of exercise has been studied extensively using plasma biochemistry but cellular data is scares. Previously, we have shown endothelial progenitor cells (EPCs) can act as a strong cellular biomarker of endothelial function following aerobic exercise as an intervention. In this study, we are examining the effect of aerobic exercise on adipocyte derived MSCs to study stromal cell differentiation and as a cellular surrogate of fat metabolism. Methods: Overweight and obese subjects (n=5) were enrolled in a 12 week exercise intervention study. The biweekly exercise sessions were supervised by a trained exercise physiologist and consisted of a 1 hour sessions that included warm-up and cool-down and 30 min of combined aerobic and resistance training at an exercise intensity of 50-80% of heart rate reserve. Physical and biochemical parameters were tested pre and post exercise. Subcutaneous abdominal fat biopsies were obtained and fat derived stromal cells were cultured in vitro for 2-3 weeks. MSCs were analyzed for mRNA gene expression (qRT-PCR) and cellular oxygen consumption rate (OCR), pre and post 12 week exercise. Results: With exercise, A1C reduced significantly. An increase of METs was also noticed post exercise. Both basal and maximal respiration increased significantly post exercise when compared with commercially obtained MSCs. Simultaneously, mitochondrial genes COX4 and ATP5B (p= 0.01, 1.4 fold, 0.02, 1.5 fold respectively), Glucose transporter, GLUT1 (p=0.04, 1.8 fold), antioxidants GPX3 and CAT (p= 0.01, 3.2 fold and p=0.04, 1.5 fold respectively) upregulated whereas pro-inflammatory cyclo-oxygenase-2 (p=0.04, 2.5 fold) gene reduced significantly, post exercise. Regarding differentiation potential of multipotent MSCs, post exercise, we noted enhanced expression of bone markers such Alkaline Phosphatase (p= 0.03, 2.7 fold) BGLAP and RUNX2 (1.3 and 1.2 fold) and also for collagen marker COL2 (2.4 fold) expression. For adipogenic differentiation potential PPARG mRNA expression was reduced. Interestingly, serum value of osteocalcin increased significantly from 15.0 (5.5) to 16.3(6.1) ng/ml (9% increase, p=0.03) with 1% increase in bone alkaline phosphatase level, post exercise. Conclusion: We conclude that exercise augments cellular glucose transporters (GLUT1), anti-oxidants and reduce MSC inflammation and up-regulates mitochondrial function and gene expression profile of MSCs. Increased serum value of osteocalcin complement increased gene expression of bone formation markers indicating a cross talk between fat derived MSCs and bone formation, post exercise.

The influence of capillarization on satellite cell pool expansion and activation following exercise-induced muscle damage in healthy young men.

Skeletal muscle stem cells (satellite cells) play a crucial role in repair and remodelling of muscle in response to exercise. Satellite cells are in close spatial proximity to muscle capillaries and therefore may be influenced by them. In this study, we describe the activation and expansion of the satellite cell pool in response to eccentric contraction-induced muscle damage in individuals with significantly different levels of muscle capillarization. Individuals with greater capillarization and capacity for muscle perfusion demonstrated enhanced activation and/or expansion of the satellite cell pool allowing for an accelerated recovery of muscle function. These results provide insight into the critical relationship between muscle capillarization and satellite cells during skeletal muscle repair. Factors that determine the skeletal muscle satellite cell (SC) response remain incompletely understood. It is known, however, that SC activation status is closely related to the anatomical relationship between SCs and muscle capillaries. We investigated the impact of muscle fibre capillarization on the expansion and activation status of SCs following a muscle-damaging exercise protocol in healthy young men. Twenty-nine young men (21±0.5years) performed 300 unilateral eccentric contractions (180degs-1 ) of the knee extensors. Percutaneous muscle biopsies from the vastus lateralis and blood samples from the antecubital vein were taken prior to (Pre) exercise and at 6, 24, 72 and 96h of post-exercise recovery. A comparison was made between subjects who had a relative low mixed muscle capillary-to-fibre perimeter exchange index (CFPE; Low group) and high mixed muscle CFPE index (High group) at baseline. Type I and type II muscle fibre size, myonuclear content, capillarization, and SC response were determined via immunohistochemistry. Overall, there was a significant correlation (r=0.39; P<0.05) between the expansion of SC content (change in total Pax7+ cells/100 myofibres) 24h following eccentric exercise and mixed muscle CFPE index. There was a greater increase in activated SCs (MyoD+ /Pax7+ cells) in the High as compared to the Low CFPE group 72h following eccentric exercise (P<0.05). The current study provides further evidence that muscle fibre capillarization may play an important role in the activation and expansion of the SC pool during the process of skeletal muscle repair.

ANALYSIS OF ACUTE RESPONSES OF LACTACIDEMY IN DIFFERENT STRENGTH TRAINING METHODS IN TRAINED MEN

Introduction: Strength training (ST) is one of the most widely practiced forms of exercise today, for individuals of different ages, of both sexes and with different levels of physical fitness. There are several reasons arising from the TF practice, however, there is a large component dedicated to aesthetics, especially to muscle hypertrophy. Objective: To analyze the acute responses of blood lactate (LAC) in different strength training methods. Methods: We evaluated 12 men with experience in strength training (age 27 ± 1.2 years, body mass 80.15 ± 6.5 kg and practice time of 4.5 ± 1.4 years). The study protocol was given by:1) anamnesis and explanation of the research; 2) 1RM test for the bench press exercise; 3) familiarization with the training protocols; 4) perform of isodynamic method (ISO), 5) perform of negative repetitions method (NGT); 6) perform of decreasing pyramid method (PRD); 7) perform of decreasing interval method (ITD); 8) perform of the rest-pause method (RST); 9) perform of wave method (OND). For the analysis of LAC in the methods, they were observed pre and post exercise which was removed 0.1 ml of blood from the right ear lobe of individuals and measured using a calibrated portable device. Results: it was observed that the acute response was statistically significant after the exercises (p 0, 12). Conclusion: Acute responses after realization of different training methods for muscle hypertrophy increased significantly LAC. Regarding the types of stress induced by exercise (TEM, TE and MIS), the LAC was no significant difference between them; however, it was observed that the methods that induce metabolic stress had greater changes in LAC. Article visualizations:

Effectiveness of air pulsed cryotherapy on delayed onset muscle soreness of elbow flexors following eccentric exercise

Cryotherapy is widely used in sports to facilitate recovery from exercise-induced muscle damage that often results from strenuous training and/or competition. However, a paucity of evidence exists on the therapeutic values of repeated air pulsed cryotherapy (CRYO) application to suggest its usefulness to clinicians, coaches, sports scientists and athletes in the field of sports and rehabilitation. Aim: This study investigates the effectiveness of CRYO on the recovery from delayed onset of muscle soreness (DOMS) induced by eccentric exercise. Materials and methods: Thirty-two participants (21.31±1.03 years; height 1.72±0.05 m; BMI 22.15±1.69 kg.cm-2) were equally randomized into CRYO group and control group (CONT). DOMS was induced by eccentric contractions of elbow flexors. Visual analogue scale score (VAS), mid arm circumference (MAC), pressure pain threshold (PPT), range of motion of active elbow flexion (ROM-AF), passive elbow flexion (ROM-PF), active elbow extension (ROM-AE), passive elbow extension (ROM-PE) and isometric peak torque of elbow flexors (IPT) were measured at pre-exercise (PRE), immediately, 1, 2, 3, 4, and 7 days post exercise. Results and discussion: There were significant interactions effect (group X time) with (P<0.05) for VAS, MAC, PPT, ROM-PF, ROM-AE, and ROMPE. Additionally, all outcome measures (except for ROM-AF and IPT) demonstrated a significant improvement (P<0.05) in DOMS recovery in the CRYO group compared to CONT group. Conclusion: A 20 minutes (4 session X5 minutes) session for 5 consecutive days of repeated air pulsed cryotherapy has beneficial effects on the recovery of DOMS on elbow flexors from eccentric exercise.

Polyphenol supplementation alters intramuscular apoptotic signaling following acute resistance exercise.

The purpose of this study was to examine the effects of 28‐days of supplementation with an aqueous proprietary polyphenol blend (PPB) sourced from Camellia sinensis on intramuscular apoptotic signaling following an acute lower‐body resistance exercise protocol and subsequent recovery. Untrained males (n = 38, 21.8 ± 2.7 years, 173.4 ± 7.9 cm, 77.6 ± 14.6 kg) were randomized to PPB (n = 14), placebo (PL; n = 14) or control (CON; n = 10). Participants completed a lower‐body resistance exercise protocol comprised of the squat, leg press, and leg extension exercises. Skeletal muscle microbiopsies were obtained from the vastus lateralis preexercise (PRE), 1‐h (1HR), 5‐h (5HR), and 48‐h (48HR) post‐resistance exercise. Apoptotic signaling pathways were quantified using multiplex signaling assay kits to quantify total proteins (Caspase 3, 8, 9) and markers of phosphorylation status (JNK, FADD, p53, BAD, Bcl‐2). Changes in markers of muscle damage and intramuscular signaling were analyzed via separate repeated measures analysis of variance (ANOVA). Change in Bcl‐2 phosphorylation at 1H was significantly greater in PL compared to CON (P = 0.001). BAD phosphorylation was significantly elevated at 5H in PL compared to PPB (P = 0.015) and CON (P = 0.006). The change in JNK phosphorylation was significantly greater in PPB (P = 0.009), and PL (P = 0.017) compared to CON at 1H, while the change for PL was elevated compared to CON at 5H (P = 0.002). A main effect was observed (P < 0.05) at 1H, 5H, and 48H for p53 and Caspase 8, with Caspase 3 and Caspase 9 elevated at 48H. These data indicate that chronic supplementation with PPB alters apoptotic signaling in skeletal muscle following acute muscle‐damaging resistance exercise.

Comparison of neuromuscular fatigue in chronic stroke patients with healthy controls

Background and Introduction: Fatigue has been defined as a feeling of early exhaustion, weariness, lack of energy and aversion to effort. Glader et al suggest that survivors of stroke with fatigue have a higher fatality rate three years after stroke due to its association with sedentary lifestyle. Neuromuscular fatigue is defined as an activity induced impairment in the ability to exert force, and is quantified by the reduction in force that a muscle or muscles can exert following or during an activity. Fatigue of the paretic leg muscles is likely to greatly impact walking function post-stroke. Therefore, quantitative measures of neuromuscular fatigue of the paretic leg muscles are expected to be associated with walking function in people post-stroke. There is scant research, which specifically investigates neuromuscular fatigue following stroke. The purpose of the study was to assess and compare the contribution of neuromuscular fatigue in patients following stroke with age and gender matched healthy participants. Methodology: Subjects (N=80) were divided into experimental group (N=40) and control group (N=40) by purposive sampling. Patients who were already been diagnosed with chronic stroke (>6months) by Registered Medical Practitioner (RMP) were included in the study. The muscle activity of the quadriceps and hamstrings on the subject’s paretic as well as non-paretic side were recorded using Dual Bio Amp/Stimulator. Pre- fatigue inducing exercise (Electromyography) EMG signals (integral mean values in mVs) were recorded by performing Maximal Voluntary Contraction (MVC) of both the muscles. Post-fatigue inducing exercise EMG signals (integral mean values in mVs) by performing Sit-To-Stand test (STS). Visual Analog Fatigue Scale (VAFS) was used to assess the subjective levels of fatigue pre and post exercise while Fatigue Severity Scale (FSS) was used to assess chronic fatigue. Results: In paretic, non-paretic and control study group, the mean pre-fatigue EMG activity of hamstrings is significantly higher compared to mean post-fatigue EMG activity of hamstrings (P-value<0.001). In paretic, non-paretic and control study group, the mean pre-fatigue EMG activity of quadriceps is significantly higher compared to mean post-fatigue EMG activity of quadriceps (P-value<0.001). Conclusion: It was concluded that there is a difference seen in the peripheral neuromuscular fatigue in the chronic stroke individuals when compared with age and gender matched control group.

Cell-Free DNA as an Earlier Predictor of Exercise-Induced Performance Decrement Related to Muscle Damage.

To evaluate whether cell-free DNA (cfDNA) levels increase immediately after an acute light and heavy resistance exercise (RE) bout and whether cfDNA levels are associated with functional muscle capacity up to 48h after an exercise session. Twenty healthy volunteers performed 3 sets of leg-press RE with 80% of 1-repetition maximum (1RM) (RE80) or 40% of 1RM (RE40) with similar exercise volume. Blood lactate was measured after completion of the 3 sets. Creatine kinase, cfDNA, and jump performance were evaluated before (pre) exercise, immediately postexercise (post-0h), and every 24h until 48h. Lactate concentration increased similarly in both groups (RE40 4.0 [1.3]mmol/L; RE80 4.8 [1.3]mmol/L). No changes were observed in squat-jump and countermovement-jump performance after RE40; however, both jumps remained reduced until 48h in the RE80 group. Creatine kinase concentration increased post-24h only in the RE80 group (pre 128.8 [73.7]U/L to post-24h 313.8 [116.4]U/L). cfDNA concentration increased post-0h only in the RE80 group (pre 249.8 [82.3]ng/mL to post-0h 406.3 [67.2]ng/mL). There was a negative correlation between post-0h cfDNA concentration and post-24h squat jump (r = -.521; P = .01) and post-0h cfDNA concentration and post-24h countermovement jump (r = -.539; P = .01). cfDNA increases in response to RE intensity even when not performed until exhaustion. cfDNA measured immediately after RE is a promising biomarker for muscle-performance decrement up to 48h after a RE bout.

PENGARUH LATIHPengaruh Latihan Fisik Terhadap Kemampuan Kognitif Lansia Di Desa Ngesrep Kecamatan Ngemplak Kabupaten BoyolaliAN FISIK TERHADAP KEMAMPUAN KOGNITIF LANSIA DI DESA NGESREP KECAMATAN NGEMPLAK KABUPATEN BOYOLALI

Abstract : Exercise, Older People, Cognitive Performance, MMSE. Cognitive performance in older people declines gradually due to aging process. It raises problems in functional daily activities, risks of injury, and dependency. Literatures have been revealed the benefits of exercise for health, not only physically, but also mentally. The purpose of this study was to determine the effect of exercise on the cognitive performance of older people in Ngesrep Village, Boyolali District. This study was a quasi experimental one group pre test- post test with control group. A constitutive sampling method was applied to get subjects, and found 20 people for each experiment and control group. The instrument used was Mini Mental State Examination (MMSE). Based on paired t-test analysis in the experiment group, it was found a significant difference on the cognitive performance pre and post exercise intervention (α = 0.05, t = 2.492, p = 0.022, r = 0.657). In the control group, there was no diferrence in pre and post test (p = 0.053). Based on independent t-test analysis between experiment and control group, it was found a significant difference before the intervention (p = 0.031), but after the intervention, there was no difference between the two groups. It was due to the increasing MMSE’s score on the experiment group, whereas the score of control group was relatively the same. Physical exercise had a significant influence on the cognitive performance of older people in this study, so it should be held in Ngesrep Village’s Posyandu routinely.