High-intensity Training Group Research Articles

Interval Versus Continuous Intradialytic Training on Muscle Quality Index and Functional Capacity in Hemodialysis Patients: a Prospective Randomized Clinical Study

INTRODUCTION. Chronic kidney disease (CKD) is an important health well-being problem globally, with increasing incidence. That tends to create an “epidemic”. Generalized muscle weakness in hemodialysis patients typically affects the lower limbs and proximal muscles. Patients experience impaired endurance and quality of life. Exercise is prescribed for these individuals to improve their physical health and prevent disease consequences. AIM. To find out the effect of interval versus continuous intradialytic training on muscle quality index and functional capacity in Hemodialysis patients. MATERIALS AND METHODS. Sixty men with chronic renal insufficiency grade 5 on hemodialysis aged from 45 to 55 years were divided into two groups using computerized block randomization: Groups (A) and (B) each containing 30 patients. They underwent 8-week program of high intensity interval training (HIIT), moderate intensity continuous training (MICT) intradialytic pedaling exercise plus hemodialysis three times per week. Pre-test and post-test evaluations have been carried out for 6-minute walk test (6MWT) and muscle quality index (MQI) of all patients. RESULTS. Both groups had a significant positive improvement in MQI and 6MWT with different proportions, patients received high intensity interval intradialytic pedaling exercise had a slightly significant improvement in MQI compared to moderate intensity continuous training group. While, moderate intensity training group had a more significant improvement in 6MWT compared to high intensity training group. CONCLUSION. Both HIIT and MICT are realistic and good options for individuals with CKD and have parallel profits on functional capability and, skeletal muscle quality and overall quality of life.

Effects of Exercise Intensities on Changes in Pro-/Anti-inflammatory Cytokines following 8-weeks of Aerobic Exercise Training

Inflammatory cytokines are useful biomarkers in predicting the development of metabolic and cardiovascular diseases and may be positively affected by physical activity and weight loss. Despite much interest in chronic low-level inflammation in the obese population, effects of aerobic training intensity on inflammatory cytokines remain elusive. PURPOSE: The purpose of this study was to investigate effects of 8-week aerobic exercise training at high and low intensities on changes in pro-/anti-inflammatory cytokines. Methods: Fifty three inactive obese Hispanic females (mean BMI = 34.5 kg/m2, aged 34-46 years) were divided into one of three groups: low intensity training group (LT: walking at 55% VO2max, n=16), high intensity training group (HT: running at 70% VO2max, n=18), and control group (CON: no intervention, n=19). LT and HT performed aerobic exercises three times per week at the given intensities. Exercise volume for two exercise groups was equated relative to kilograms of body weight by adjusting duration of exercise session (approximately 60 minutes for LT and 40 minutes for HT per session). Blood samples were collected before and after 8 weeks of intervention to measure levels of adiponectin, C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-α). Two-way repeated measures ANOVA and Tukey post hoc tests were used for data analysis. Results: Level of adiponectin showed no significant change in any groups after 8 weeks of aerobic exercise intervention. A significant decrease in CRP was observed in the HT group only (4.12 ±.26mg/L mean±SE → 3.89±.37, P=.041), but levels of TNF-a were significantly decreased in both LT (4.57±.24pg/mL → 4.14±.31, P=.019) and HT (4.54±.25 → 4.02±.41, P=.011). No changes were observed in CON. CONCLUSIONS: Significant decreases in CRP and TNF-a were found following high intensity aerobic exercise training while low intensity training reduced TNF-a only. The greater changes of pro-inflammatory cytokines in HT indicates high intensity aerobic exercise training may be more beneficial than low intensity training. Specifically, for controlling low-grade inflammation and immune function in obese Hispanic females. This study confirmed results of previous studies suggesting that longer period of exercise training with distinct fat loss may be required to induce significant changes in adiponectin in obese adults. TAMIU university research grant. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The adaptation of glucose levels to high-intensity interval training and moderate-intensity training methods in obese male adolescents

This study aimed to show the effectiveness of high-intensity training (HIIT) and moderate-intensity training (MIT) on glucose levels in obese adolescents. This research was a true experimental study with a pretest-posttest control group design. Treatment in the form of HIIT and MIT was given to the sample for four weeks. While the control group was not given any treatment. The Glucose Oxsidase – Peroxidase Aminoantypirin (GOD PAP) reagent tested glucose levels using a venous sugar blood test. The treatment was conducted at the Bung Hatta Ngawi Sports Center, East Java, Indonesia. This study used 45 obese male adolescents with type 1 body mass index of 25-29 kg/m2. Forty-five samples were divided into three groups, including 15 MIT groups, 15 HIIT groups, and 15 controls. The data analysis test used ANOVA using SPSS V.26 with a significance of 0.05. The results showed that there was a significant difference in glucose levels before and after the treatment (p=0.000). HIIT was better than MIT, with a pre and post-test difference of 33.35 (HIIT) and 23.20 (MIT) respectively. HIIT with a maximum intensity of 80% was the right choice as an alternative treatment for obesity during a pandemic. The results of the study can be concluded that HIIT was more effective in influencing glucose levels in obese adolescents than MIT.

Dose-response effects of exercise on mental health in community-dwelling older adults: Exploration of genetic moderators

Background/Objective(1) Examine the role of exercise intensity on mental health symptoms in a community-based sample of older adults. (2) Explore the moderating role of genetic variation in brain-derived neurotrophic factor (BDNF) and apolipoprotein E (APOE) on the effects of exercise on mental health symptoms. MethodThis study is a secondary analysis of a three-arm randomized controlled trial, comparing the effects of 6 months of high-intensity aerobic training vs. moderate-intensity aerobic training vs. a no-contact control group on mental health symptoms assessed using the Depression, Anxiety, and Stress Scale (DASS). The BDNF Val66Met polymorphism and APOE ε4 carrier status were explored as genetic moderators of exercise effects on mental health symptoms. ResultsThe exercise intervention did not influence mental health symptoms. The BDNF Val66Met polymorphism did not moderate intervention effects on mental health symptoms. APOE ε4 carrier status moderated the effect of intervention group on perceived stress over 6 months, such that APOE ε4 carriers, but not non-carriers, in the high-intensity aerobic training group showed a decline in perceived stress over 6 months. ConclusionsAPOE ε4 carrier status may modify the benefits of high-intensity exercise on perceived stress such that APOE ε4 carriers show a greater decline in stress as a result of exercise relative to non-APOE ε4 carriers.

Comparing low volume of blood flow restricted to high-intensity resistance training of the finger flexors to maintain climbing-specific strength and endurance: a crossover study.

It is acknowledged that training during recovery periods after injury involves reducing both volume and intensity, often resulting in losses of sport-specific fitness. Therefore, this study aimed to compare the effects of high-intensity training (HIT) and low-intensity training with blood flow restriction (LIT + BFR) of the finger flexors in order to preserve climbing-specific strength and endurance. In a crossover design, thirteen intermediate climbers completed two 5-week periods of isometric finger flexors training on a hangboard. The trainings consisted of ten LIT + BFR (30% of max) or HIT sessions (60% of max without BFR) and were undertaken in a randomized order. The training session consisted of 6 unilateral sets of 1 min intermittent hanging at a 7:3 work relief ratio for both hands. Maximal voluntary contraction (MVC), force impulse from the 4 min all out test (W), critical force (CF) and force impulse above the critical force (W') of the finger flexors were assessed before, after the first, and after the second training period, using a climbing-specific dynamometer. Forearm muscle oxidative capacity was estimated from an occlusion test using near-infrared spectroscopy at the same time points. Both training methods led to maintaining strength and endurance indicators, however, no interaction (P > 0.05) was found between the training methods for any strength or endurance variable. A significant increase (P = 0.002) was found for W, primarily driven by the HIT group (pretest-25078 ± 7584 N.s, post-test-27327 ± 8051 N.s, P = 0.012, Cohen's d = 0.29). There were no significant (P > 0.05) pre- post-test changes for MVC (HIT: Cohen's d = 0.13; LIT + BFR: Cohen's d = -0.10), CF (HIT: Cohen's d = 0.36; LIT + BFR = 0.05), W` (HIT: Cohen's d = -0.03, LIT + BFR = 0.12), and forearm muscle oxidative capacity (HIT: Cohen's d = -0.23; LIT + BFR: Cohen's d = -0.07). Low volume of BFR and HIT led to similar results, maintaining climbing-specific strength and endurance in lower grade and intermediate climbers. It appears that using BFR training may be an alternative approach after finger injury as low mechanical impact occurs during training.

Effects of adding high-intensity training during an 8-week period on maximal oxygen uptake in 12-year-old youth athletes.

Maximal oxygen uptake (V̇O2max ) increases during adolescence parallel to the increase in fat-free mass (FFM). How much endurance training adds to this effect is still controversial. Our aim was to investigate if inclusion of high-intensity training (HIT) during an 8-week training period was superior to low-intensity strength and coordination training in 12-year-old youth athletes concerning the effect on V̇O2max . Thirty-five cross-country skiers were randomized into a HIT group (ET) and a strength and coordination group (SC), while 29 less active peers served as controls for growth and maturation (C). Anthropometrics and V̇O2max were assessed before and after the training period, and level of physical activity and training were monitored with accelerometers, training logs and a questionnaire. The number of weekly training sessions were higher for ET (4.6 ± 1.2) and SC (4.1 ± 1.0) compared with C (1.8 ± 2.0) (p < 0.01), with only ET conducting HIT sessions (1.9 ± 0.2 per week). C spent more time sedentary and less time in moderate and vigorous activity compared with ET (p < 0.05). All groups had a similar %-change pre-post in absolute V̇O2max (mL min-1 ) of 6% ± 6% for ET (p < 0.01), 5% ± 7 for SC (p = 0.14), and 5% ± 13% for C (p = 0.03), with no significant differences between groups. V̇O2max relative to FFM did not change significantly for any groups. The change in V̇O2max paralleled the change in FFM for all groups, questioning the effect of HIT on V̇O2max over an 8-week period in youth athletes.

Effects of blood flow restriction training on bone turnover markers, microstructure, and biomechanics in rats.

The present study aimed to investigate the effects of blood flow restriction training on muscle strength, bone tissue structure material, and biomechanical properties in rats applying various exercise interventions and to analyze the process by identifying the bone turnover markers, it provides a theoretical basis for the application of BFRT in clinical rehabilitation. A total of 24, 3-month-old male SD (Sprague Dawley) rats were randomly divided into pressurized control group (CON, n=6), low-intensity training group (LIRT, n=6), high-intensity training group (HIRT, n=6), and blood flow restriction training group (LIBFR, n=6) for 8-week ladder-climbing exercises. The pressured control group were given only ischemia treatments and did not undertake any burden. The low-intensity training group was allowed to climb the ladder with 30% of the maximum voluntary carrying capacity (MVCC). The rats in the high-intensity training group were allowed to climb the ladder with 70% MVCC. The blood flow restriction training group climbed the ladder with 30% MVCC while imposing blood flow restriction. Before sampling, the final MVCC was measured using a ladder-climbing protocol with progressively increasing weight loading. The serum, muscle, and bone were removed for sampling. The concentrations of the bone turnover markers PINP, BGP, and CTX in the serum were measured using ELISA. The bone mineral density and microstructure of femur bones were measured using micro-CT. Three-point bending and torsion tests were performed by a universal testing machine to measure the material mechanics and structural mechanics indexes of the femur bone. The results of maximum strength test showed that the MVCC in LIRT, HIRT, and LIBFR groups was significantly greater than in the CON group, while the MVCC in the HIRT group was significantly higher than that in the LIRT group (P<0.05). According to the results of the bone turnover marker test, the concentrations of bone formation indexes PINP (amino-terminal extension peptide of type I procollagen) and BGP (bone gla protein) were significantly lower in the CON group than in the HIRT group (P<0.01), while those were significantly higher in the LIRT group compared to the HIRT group (P<0.01). In terms of bone resorption indexes, significant differences were identified only between the HIRT and other groups (P<0.05). The micro-CT examination revealed that the HIRT group had significantly greater bone density index values than the CON and LIRT groups (P<0.05). The results of three-point bending and torsion test by the universal material testing machine showed that the elastic modulus and maximum load indexes of the HIRT group were significantly smaller than those of the LIBFR group (P<0.05). The fracture load indexes in the HIRT group were significantly smaller than in the LIBFR group (P<0.05). 1. LIRT, HIRT, LIBFR, and CON all have significant differences, and this training helps to improve maximum strength, with HIRT being the most effective. 2. Blood flow restriction training can improve the expression of bone turnover markers, such as PINP and BGP, which promote bone tissue formation. 3. Blood flow restriction training can improve muscle strength and increase the positive development of bone turnover markers, thereby improving bone biomechanical properties such as bone elastic modulus and maximum load.

Different Continuous Training Intensities Improve Echocardiographic Parameters, Quality of Life, and Functional Capacity in Heart Failure Patients with Reduced Ejection Fraction.

Multiple comorbidities and physiological changes play a role in a range of heart failure conditions and influence the most effective approach to exercise-based rehabilitation. This research aimed to examine and compare the outcomes of continuous training at three different intensities, focusing on left ventricular (LV) remodeling, functional capacity, and quality of life among patients with heart failure with reduced ejection fraction (HFrEF). In this randomized control trial, a total of 60 male patients (average age: 54.33 ±2.35 years) with HFrEF were randomly allocated into three groups: 1) High-intensity continuous training group (HICT), 2) Moderate-intensity continuous training group (MICT), and 3) Low-intensity continuous training group (LICT). All the training was performed on a bicycle ergometer 3 times/week for 12 weeks. Echocardiographic parameters (left ventricular ejection fraction, left ventricular end-diastolic dimension, left ventricular end-systolic dimension, N-terminal pro-B-type natriuretic peptide (NT-proBNP), quality of life (Minnesota Living with Heart Failure Questionnaire), and functional capacity (6-minute walking test) were assessed before and the end of the study. The HICT group demonstrated the greatest improvements in all measured variables when compared to the other two groups (P < 0.05). These findings were consistent across all measured outcomes. It was determined that HICT appears to yield the most favorable outcomes in enhancing echocardiographic measures, NT-proBNP levels, quality of life, and functional capacity among HFrEF patients.

The restorative effects of graded intensities of exercise training on the biochemical and nutritional status of obese induced male Wistar rats (Rattus novegicus)

The purpose of this study was to evaluate the specific effects of 12 weeks of intensive, graded intensities of exercise training on nutritional parameters and some plasma biochemical parameters in high-fat diet and sucrose obesity-induced (HFDS) Wistar rats. In evaluating the restorative effects of graded exercise training as an intervention in managing obesity, 25 male Wistar rats who were 7 weeks old were used. These 25 rats were broadly grouped into 5 rats as controls and 20 rats as experiments. In the first phase of the experiment, which involved the induction of obesity, the rats were fed on HFDS containing 35% total fat, 39% carbohydrates, 23% protein, 6% fiber per 100 grams, and 60% sucrose solution per 100 mL for 12 weeks, while the 5 rats in the control group were fed on a normal rodent diet containing 5% total fat, 39% carbohydrates, 23% protein, and 6% fiber per 100 grams. In the second phase, which was the interventional phase, the 20 HFDS-induced obese rats were randomly assigned into 4 groups: the control (sedentary group), low, medium, and high-intensity exercise training groups, and were subjected to various intensities of exercise training. All experimental groups received the HFDS throughout the exercise training period. After 84 days of exercise training intervention, the final body weight, plasma biochemical parameters including total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDLC) concentrations, and nutrition parameters including feed efficiency (FE), feed consumption (FC), and caloric intake (CI) were assessed. The study established that graded exercise training has a direct, inversely proportional reduction in TC, TG, and LDLC concentrations. In conclusion, medium- to high-intensity exercise training is associated with restoring the dyslipidemic profile in the serum of rats and also increased feed efficiency.

Cartilage tissue turnover increases with high- compared to low-intensity resistance training in patients with knee OA

ObjectivesTo investigate cartilage tissue turnover in response to a supervised 12-week exercise-related joint loading training program followed by a 6-month period of unsupervised training in patients with knee osteoarthritis (OA). To study the difference in cartilage tissue turnover between high- and low-resistance training.MethodPatients with knee OA were randomized into either high-intensity or low-intensity resistance supervised training (two sessions per week) for 3 months and unsupervised training for 6 months. Blood samples were collected before and after the supervised training period and after the follow-up period. Biomarkers huARGS, C2M, and PRO-C2, quantifying cartilage tissue turnover, were measured by ELISA. Changes in biomarker levels over time within and between groups were analyzed using linear mixed models with baseline values as covariates.ResultshuARGS and C2M levels increased after training and at follow-up in both low- and high-intensity exercise groups. No changes were found in PRO-C2. The huARGS level in the high-intensity resistance training group increased significantly compared to the low-intensity resistance training group after resistance training (p = 0.029) and at follow-up (p = 0.003).ConclusionCartilage tissue turnover and cartilage degradation appear to increase in response to a 3-month exercise-related joint loading training program and at 6-month follow-up, with no evident difference in type II collagen formation. Aggrecan remodeling increased more with high-intensity resistance training than with low-intensity exercise.These exploratory biomarker results, indicating more cartilage degeneration in the high-intensity group, in combination with no clinical outcome differences of the VIDEX study, may argue against high-intensity training.

Effect of blood flow-restricted resistance training on myocardial fibrosis in early spontaneously hypertensive rats.

The purpose of this study was to explore the effect of blood flow-restricted resistance training on myocardial fibrosis in early spontaneously hypertensive rats (SHRs). Four-week-old male Wistar-Kyoto rats and SHRs were randomly divided into the following groups: normal group (WKY), SHR control (SHR-SED) group, high-intensity resistance training (HIRT) group, low- and medium-intensity resistance training (LMIRT) group, and blood flow-restricted low- and medium-resistance training (BFRT) group. Body weight, hemodynamics, cardiac function, myocardial morphology and fibrosis, and the expression levels of transforming growth factor-beta1-Smad (TGFβ-1-Smad) pathway-related proteins in the myocardium were assessed. (1) BFRT lowered blood pressure significantly, decreased left ventricular wall thickness, and improved cardiac function. At the same time, BFRT was superior to traditional resistance training in lowering diastolic blood pressure, and was superior to HIRT in improving left ventricular compliance, reducing heart rate, and reducing left ventricular posterior wall and left ventricular mass (P < 0.05). (2) BFRT decreased collagen I and collagen fiber area in the myocardium, increased the collagen III area, and decreased the collagen I/III ratio (P < 0.05). BFRT produced a better proportion of myocardial collagen fibers than did traditional resistance training (P < 0.05). (3) In the myocardium of the BFRT group compared to the traditional resistance training group, the expression of TGFβ-1, Smad2/3/4, p-Smad2/3, CTGF, and TIMP1 was significantly downregulated, MMP2 and TIMP2 were significantly upregulated, the MMP/TIMP ratio significantly increased, and TGFβ-1 expression significantly decreased (P < 0.05). BFRT inhibited the TGFβ-1-Smad pathway in the myocardium, downregulated the expression of CTGF, and regulated the balance between MMPs and TIMPs, thereby reducing myocardial fibrosis in SHR, and improving cardiac morphology and function. BFRT also lowered blood pressure, and achieved an effect of early prevention and treatment of hypertension. At the same time, BFRT was superior to traditional resistance training in reducing diastolic blood pressure and adjusting the proportion of myocardial collagen fibers.

Training, detraining and retraining effects of moderate vs. high intensity exercise training programme on cardiovascular risk factors.

The aim of the present study was to analyse the effect of 12 weeks of training, 7 weeks of detraining and 16 weeks of retraining using a moderate or high intensity training programme on cardiovascular risk factors in hypertensive patients. Thirty-four patients took part in the study. The intensity training was 80-90% of maximum heart rate for the high-intensity training (HIT) group ( n = 15) and at 50-70% of maximum heart rate for the moderate training (MT) group ( n = 19). Blood pressure, body composition, lipid profile, fasting glucose, strength and cardiovascular fitness were analysed. The first training period did not decrease blood pressure, but the second training period saw significant decreases in blood pressures in HIT group. Moreover, 12 weeks of MT or HIT did not decrease body mass, body mass index or fat mass. However, after 7 weeks of detraining, the inclusion of a second training period using HIT saw decreases in these body composition variables. Both training periods and intensities improved high-density lipoprotein and low-density lipoprotein, but only HIT decreased total cholesterol. In addition, after 7 weeks of detraining, the lipid profile variables returned to baseline values. Additionally, 16 weeks of retraining with HIT or MT decreased blood glucose significantly. Moreover, MT and HIT training programmes in both periods improved cardiorespiratory fitness, but with 7 weeks of detraining, it returned to baseline values. Our data demonstrated the effectiveness of the inclusion of a MT or HIT programme as adjuvant therapy in hypertensive patients.

The Impact of Exercise Training Intensity on Physiological Adaptations and Insulin Resistance in Women with Abdominal Obesity.

Abdominal obesity has emerged globally as a major public health issue due to its high prevalence and morbidity. The benefits of physical exercise among the obese population are well documented. However, the optimal exercise intensity for reducing body fat and preventing insulin resistance and metabolic disorders is still under debate. This study aimed to examine the effects of three different intensities of combined endurance and strength training programs on anthropometric variables, physiological and muscular adaptations, and insulin sensitivity. Forty-three obese young women (age 26.4 ± 4.7 years, BMI 33.1 ± 2.5 kg/m2) were randomly assigned to one of four groups: a control group (G0), a moderate-intensity training group (G50, exercising brisk walking at 50% heart rate reserve HRR), a high-intensity training group (G75, exercise jogging at 75% HRR), and an alternated-intensity training group (G50/75, exercise brisk-walking/jogging at 50-75% HRR) with additional strength training once a week for each group. Body composition, waist circumference (WC), fasting blood glucose, insulin sensitivity and resistance (Homa-IR), resting heart rate (RHR), 6-min walk distance (6MWD), 1-repetition maximum (1-RM), and time to exhaustion (TTE) at 45% and 75% maximal voluntary contraction (MVC) for both the flexor and extensor muscle groups of the knees, were recorded before and after three months of exercise training. All training groups showed significant decreases in body mass, BMI, total body fat, body fat percentage, WC, abdominal and visceral mass (p &lt; 0.001), with a greater reduction of body mass and BMI in G75 (p &lt; 0.05). Lean mass increased significantly only in G50/75 (p &lt; 0.05). The insulin sensitivity and Homa-IR decreased in the three training groups (p &lt; 0.01), with greater enhanced resistance in G50 compared to G75 and G50/75 (p &lt; 0.05). In contrast, there were no pre-post changes in all groups for fasting blood glucose (p &gt; 0.05). 1-RM and TTE of the knee flexor and extensor muscles were improved in the three groups (p &lt; 0.01), with greater improvement in G50/75 for 1RM and G75 in most of the TTE parameters (p &lt; 0.05). RHR decreased and 6MWD increased significantly in the three training groups (p &lt; 0.01), with greater 6MWD improvement in G75 (p &lt; 0.05). In conclusion, the three training intensities seem to generate benefits in terms of body composition, physiological and muscular adaptations, and insulin resistance. High training intensity resulted in greater improvements in body mass, BMI, and endurance and strength, whereas moderate training intensity resulted in greater improvements of insulin resistance and homo-IR. Following alternate-intensity training, greater improvements were observed in lean mass and maximal strength performance.

Effects of High and Low-To-Moderate Intensity Exercise During (Neo-) Adjuvant Chemotherapy on Muscle Cells, Cardiorespiratory Fitness, and Muscle Function in Women With Breast Cancer: Protocol for a Randomized Controlled Trial.

(Neo-)adjuvant chemotherapy for breast cancer is effective but has deleterious side effects on muscle tissue, resulting in reduced skeletal muscle mass, muscle function, and cardiorespiratory fitness. Various exercise regimens during cancer treatment have been shown to counteract some of these side effects. However, no study has compared the effect of high-intensity training versus low-to-moderate intensity training on muscle tissue cellular outcomes and physical function in patients with breast cancer during chemotherapy. The aim of this substudy within the Physical Training in Cancer (Phys-Can) consortium is to evaluate and compare the effects of high and low-to-moderate intensity exercise on muscle cellular outcomes, muscle function, and cardiorespiratory fitness in women with breast cancer undergoing (neo-)adjuvant chemotherapy. We further aim to investigate if the effects of chemotherapy including taxanes on muscles will be different from those of taxane-free chemotherapy. Eighty women recently diagnosed with breast cancer scheduled to start (neo-)adjuvant chemotherapy will be randomized to a combination of strength and endurance training, either at high intensity or at low-to-moderate intensity. Testing of muscle function and cardiorespiratory fitness and collection of muscle biopsies from the vastus lateralis muscle will be performed before the first cycle of chemotherapy (or after 1 week, when not possible) (T0), halfway through chemotherapy (T1), and after completion of chemotherapy (T2). It is estimated that approximately 50% of the participants will be willing to undergo muscle biopsies. To separate the effect of the treatment itself, a usual care group with no supervised training will also be included, and in this group, testing and collection of muscle biopsies will be performed at T0 and T2 only. This study is funded by Active Against Cancer (Aktiv mot kreft) (May 2013) and the Norwegian Cancer Society (December 2018). Inclusion started in December 2016 and the last participant is expected to be recruited in December 2022. As of June 2022, we enrolled 38 (19 with biopsies) participants to the high-intensity training group, 36 (19 with biopsies) participants to the low-to-moderate intensity training group, and 17 (16 with biopsies) participants to the usual care group. Data analyses will start in fall 2022. The first results are expected to be published in spring 2024. This study will generate new knowledge about the effects of different training intensities for women with breast cancer during chemotherapy treatment. It will give further insight into how chemotherapy affects the muscle tissue and how physical training at different intensities may counteract the treatment side effects in muscles. The results of this study will inform the development and refinement of exercise programs that are effective and compatible with the multidisciplinary management of breast cancer. ClinicalTrials.gov NCT05218876; https://tinyurl.com/ysaj9dhm. DERR1-10.2196/40811.

The Effects of Eight Weeks Moderate- and High-Intensity Circuit Resistance Training on the Levels of Serum Amyloid A and Insulin Resistance in Sedentary Men

Introduction: Obesity-related inflammation has an important role in increasing the risk of various pathological conditions, including insulin resistance. In this study, the effects of 8 weeks of moderate and high-intensity circuit resistance training on the levels of serum amyloid A (SAA) and insulin resistance were investigated in sedentary men.Methods: In this study, 36 sedentary men (average BMI: 30.64 ± 3.14 kg/m2, age of 20 to 35 years old) were randomly assigned to the control (C), moderate-intensity circuit resistance training (MRT), and high-intensity circuit resistance training (HRT) groups. The training protocol was performed during eight weeks (three sessions per week). Blood samples were collected before and after eight weeks of training, and serum levels of SAA, insulin, and glucose were measured. The data were analyzed by SPSS-24 software using the analysis of covariance (ANCOVA) test with the Bonferroni post hoc test.Results: The present study’s findings indicated that SAA levels and insulin resistance significantly reduced in the HRT and MRT groups compared to the control group (P &lt; 0.001). However, our results showed that the changes observed in SAA and insulin resistance were not significantly different between the HRT and MRT groups (P &gt; 0.05).Conclusion: It seems that HRT has no extra effects on inflammation and insulin resistance compared to MRT; however, changes in the levels of other inflammatory mediators should be determined.

High-intensity Training And A Low-caloric-diet Improves Maximal Oxygen Consumption And Body Composition In Overweight Adults

Obesity and low cardiorespiratory fitness are global challenges causing a massive burden on the health care system worldwide. Thus, efficient exercise and nutritional interventions are warranted. PURPOSE: We investigate the effect of high-intensity training executed as full body circuit training and a calorie-restricted diet plan on cardiorespiratory fitness and body composition in overweight sedentary adults. METHODS: Sedentary overweight men (n = 34) and women (n = 46) were recruited. The selection criteria were a sedentary lifestyle for the last five years, an age range of 25-55 yrs and a body mass index >25. The study was a randomized controlled trial, where participants were randomized gender-specifically into a high-intensity training group (HIT; age 38 ± 9 (25-54) yrs; height 174 ± 10 cm; weight 96.1 ± 19.3 kg; n = 40) and control group (CON; age 39 ± 7 (27-52) yrs, height 168 ± 8 cm, weight 89.9 ± 17.2 kg; n = 40). HIT completed full-body high-intensity circuit training with 2-4 weekly sessions combined with a calorie-restricted dietary plan for 8 wks. CON had no training or lifestyle changes in the same interval. VO2max-tests and body composition assessments were performed at baseline and post-intervention. RESULTS: VO2max was 2.3 ± 0.6 and 2.1 ± 0.5 L⸱min-1 at baseline in HIT and CON respectively and did not change during the intervention period. However, VO2max adjusted for body weight improved (P < 0.05) by ~7% in HIT (24.5 ± 5.1 vs 25.7 ± 5.5 ml⸱min-1⸱kg-1) during the intervention period with greater (P < 0.05) change score than CON where a reduction (P < 0.05) of ~5% (24.1 ± 5.1 vs 22.6 ± 4.6 ml⸱min-1⸱kg-1) was observed. Body weight decreased (P < 0.05) by 5.9 ± 3.2 kg post-intervention in HIT with higher (P < 0.05) change score than CON (+0.3 ± 1.6 kg). Also, BMI declined (P < 0.05) from 31.8 ± 5.5 to 29.9 ± 4.4 kg/m2 in HIT only. Body fat content was also lowered (P < 0.05) from 32.0 ± 9.5% at baseline to 30.9 ± 9.3% post-intervention in HIT with a greater change score compared to CON. No change was observed in skeletal muscle mass in neither HIT nor CON. CONCLUSION: High-intensity training performed as full body circuit training combined with a caloric-restricted diet over an eight-week period moderately improved body weight adjusted VO2max, but induced a marked weight loss and reduction in body fat content in overweight sedentary adults.

Gains in Daily Stepping Activity in People With Chronic Stroke After High-Intensity Gait Training in Variable Contexts.

Many physical therapist interventions provided to individuals with chronic stroke can lead to gains in gait speed or endurance (eg, 6-Minute Walk Test [6MWT]), although changes in objective measures of participation are not often observed. The goal of this study was to determine the influence of different walking interventions on daily stepping (steps per day) and the contributions of demographic, training, and clinical measures to these changes. In this secondary analysis of a randomized clinical trial, steps per day at baseline and changes in steps per day following 1 of 3 locomotor interventions were evaluated in individuals who were ambulatory and >6months after stroke. Data were collected on 58 individuals who received ≤30 sessions of high-intensity training (HIT) in variable contexts (eg, tasks and environments; n = 19), HIT focused on forward walking (n = 19), or low-intensity variable training (n = 20). Primary outcomes were steps per day at baseline, at post-training, and at a 3-month follow-up, and secondary outcomes were gait speed, 6MWT, balance, and balance confidence. Correlation and regression analyses identified demographic and clinical variables associated with steps per day. Gains in steps per day were observed across all groups combined, with no between-group differences; post hoc within-group analyses revealed significant gains only following HIT in variable contexts. Both HIT groups showed gains in endurance (6MWT), with increases in balance confidence only following HIT in variable contexts. Changes in steps per day were associated primarily with gains in 6MWT, with additional associations with baseline 6MWT, lower-extremity Fugl-Meyer scores, and changes in balance confidence. HIT in variable contexts elicited gains in daily stepping, with changes primarily associated with gains in gait endurance. Providing HIT in variable contexts appears to improve measures of participation (eg, daily stepping) that may be associated with clinical measures of function. Gains in multiple measures of mobility and participation with HIT in variable contexts may improve the efficiency and value of physical therapy services.

Effects of Different Intensity Exercise on the Patients of Oxidative Stress Factors and Glycemic Control Type 2 Diabetes Mellitus

This study’s major purpose was to examine the impact of two various exercise intensities on glucagon-like peptide-1 and endoplasmic reticulum stress in teenagers with type 2 diabetes. Twenty teenagers with T2DM were recruited in the trial and randomly assigned to one of two groups: HIT (n = 10) or LIT (n = 10). At a heart rate of less than 45 percent, the low-intensity intense exercise group participated in aerobic activity training. Interval training with a heart rate reserve of at least 80% was used by the high-intensity intermittent training group. Both groups had the same weekly energy expenditure (1,200 kcal/week). The nositol required enzyme 1 and X-box binding protein-1 improved in both groups, but the difference in improvement between the two groups was not statistically significant. High-intensity interval training led to a significant decrease in body fat percentage among participants. After 12 weeks, the C-peptide levels had risen and varied considerably between the two groups. According to the homeostasis model assessment, there were significant differences between the groups in fasting glucose and insulin resistance, and leptin levels reduced after 12 weeks. The 12-week rise in glucagon-like peptide-1 was different across the groups. In teenagers with type 2 diabetes mellitus, high-intensity intermittent exercise training may enhance glycemic management, physical body composition, glucagon-like peptide-1, and endoplasmic reticulum stress.

How Do the Effects of an 8-Week Intervention Influence Subsequent Performance Development in Cross-Country Skiers?

To investigate how the effects of increased low- versus high-intensity endurance training in an 8-week intervention influenced the subsequent development of performance and physiological indices in cross-country skiers. Forty-four (32 men and 12 women) junior cross-country skiers were randomly assigned into a low-intensity training group (LITG, n = 20) or high-intensity training group (HITG, n = 24) for an 8-week intervention followed by 5 weeks of standardized training with similar intensity distribution, and thereafter 14 weeks of self-chosen training. Performance and physiological indices in running and in roller-ski skating were determined preintervention, after the intervention, and after the standardized training period. Roller-ski skating was also tested after the period of self-chosen training. No between-groups changes from preintervention to after the standardized training period were found in peak speed when incremental running and roller-ski skating (P = .83 and .51), although performance in both modes was improved in the LITG (2.4% [4.6%] and 3.3% [3.3%], P < .05) and in roller-ski skating for HITG (2.6% [3.1%], P < .01). While improvements in maximal oxygen consumption running and peak oxygen uptake roller-ski skating were greater in HITG than in LITG from preintervention to after the intervention, no between-groups differences were found from preintervention to after the standardized training period (P = .50 and .46), although peak oxygen uptake in roller-ski skating significantly improved in HITG (5.7% [7.0%], P < .01). No changes either within or between groups were found after the period of self-chosen training. Differences in adaptations elicited by a short-term intervention focusing on low- versus high-intensity endurance training had little or no effect on the subsequent development of performance or physiological indices following a period of standardized training in cross-country skiers.

Investigating the Effect of Vitamin D and Calcium Supplementation Along With High-intensity Circuit Training on Lipid Profile and Body Fat in Overweight Elderly

Aims Lifestyle changes, such as dietary modifications and exercise, are highly recommended for managing dyslipidemia. This study aims to investigate the combined effects of high-intensity circuit training along with vitamin D and calcium supplementation on body fat and plasma lipid profiles in overweight elderly. Methods &amp; Materials A total of 47 elderly subjects were randomly divided into 4 groups based on their body mass index as follows: Vitamin D and calcium supplementation+high-intensity circuit training group (D+Ca+T: n=12); high-intensity circuit training+placebo (T+P: n=13); vitamin D and calcium supplementation (D+Ca: n=12); and control group (CON: n=10). The subjects in the D+Ca group respectively received vitamin D and Ca supplements at 50 000 IU per week and 1000 mg per day for 8 weeks. Meanwhile, the subjects in training groups exercised 3 times per week for 8 weeks. The subjects in the D+Ca+T group participated in both treatments. The control group was instructed to maintain their regular daily routine throughout the study period. Body fat and blood lipid levels were assessed at the beginning of the study and after the 8-week intervention. Findings The D+Ca+T, T+P, and D+Ca groups exhibited significant reductions in body fat percentage (P≤0.05), while no significant changes were observed in the control group. Additionally, total cholesterol, triglycerides, High-density lipoprotein cholesterol, and low-density lipoprotein cholesterol significantly improved in the D+Ca+T, T+P, and D+Ca groups (P≤0.05), with no significant changes observed in these variables in the control group. Conclusion The results showed that high-intensity circuit training, vitamin D, and calcium supplementation would positively affect body fat and blood lipid profiles in overweight elderly. Moreover, vitamin D and calcium supplementation were especially effective when combined with exercise training.