High-intensity Circuit Training Research Articles

Effect of high intensity circuit training on muscle mass, muscular strength, and blood parameters in sedentary workers.

The study aim was to investigate the effect of high intensity circuit training on body composition, muscular performance, and blood parameters in sedentary workers. A total of 36 middle-aged sedentary female workers were randomly divided into high intensity circuit training (HICT) group, aerobic training (AT) group, and control (CON) group. The exercise training groups performed exercise three times per week for 8 weeks. In HICT, each session was 20-35 min with 2-3 rounds. Rounds were 8 min; the interval between rounds was 4-5 min. In AT, each exercise session comprised 20-35 min of aerobic dance training. Physiological parameters were measured 1 week before and after the interventions. The resulting data were analyzed using two-way mixed design ANOVA, the differences in body composition, muscular performance and blood parameters before and after training were compared. The muscle mass (pre-test: 21.19 ± 2.47 kg; post-test: 21.69 ± 2.46 kg, p < 0.05) and knee extension 60°/s (pre-test: 82.10 ± 22.26 Nm/kg; post-test: 83.47 ± 12.83 Nm/kg, p < 0.05) of HICT group were significantly improved, with knee extension 60°/s significantly higher than that of the CON group (HICT: 83.47 ± 12.83 Nm/kg; CON: 71.09 ± 26.53 Nm/kg). In the AT group, body weight (BW) decreased significantly (Pre-test: 59.37 ± 8.24 kg; Post-test: 58.94 ± 7.98 kg); no significant change was observed in CON group. The groups exhibited no significant change in blood parameters (hs-CRP, TC, and LDL-C) or IGF-1. Sedentary worker's muscle mass and lower-limb muscular performance were effectively improved by performing 8-week HICT with the benefits of short duration, no spatial constraints, and using one's BW, whereas AT caused a significant decrease in BW. However, the AT induced decrease in BW was probably an effect of muscle loss rather than exercise-induced weight loss.

The effect of high-intensity circuit training on physical fitness in healthy young males

Sedentism, along with a lack of physical activity, contributes to a decline in quality of life and is the fourth greatest cause of mortality. Changing sedentary lifestyle choices, such as increased physical exercise, is a method of health problem prevention. As a result, the purpose of this study is to investigate the effect of high-intensity circuit training on developing physical fitness in young healthy guys. A proper experimental procedure was employed in this investigation, including a pre-test - post-test control group design. Twenty Malang City students aged 19 to 22 were selected and separated into CNTL (control group) and HICT (high-intensity circuit training group). The high-intensity circuit training (HICT) intervention was performed three times per week for eight weeks. Physical fitness (VO2max, strength, speed, and agility) was assessed pre- and post-intervention. An independent sample t-test with a significance threshold of 5% is used in the data analysis procedure. The findings revealed a delta (∆) difference in the average gain in physical fitness (VO2max, strength, speed, and agility) between CNTL and HICT (p ≤ 0.01). This study shows that high-intensity circuit training done three times per week for eight weeks improves physical fitness in healthy young males. Keywords: Healthy male; high-intensity circuit training; physical fitness; sedentary lifestyle

A Description of Exercise Programs Implemented During a Firefighter Training Academy.

The aim of the study is to thoroughly describe exercise programs that were performed during a firefighter training academy, including their effects on body composition and physical fitness. Fourteen recruits performed exercise programs during a 24-week training academy and several components of their body composition and physical fitness were measured. Moreover, their heart rate (HR) and session rating of perceived exertion (sRPE) were recorded during and after every training session, respectively. Fat-free mass, subcutaneous fat in the abdomen, cardiovascular fitness, flexibility, lower-body power, and muscular endurance significantly improved during the study ( P ≤ 0.05). The highest HR and sRPE responses were observed during aerobic training (AT) sessions. The average HR responses relative to maximum HR were similar during AT, high-intensity circuit training, multimodal high-intensity interval training, and high-intensity functional training; however, the sRPEs during high-intensity circuit training and multimodal high-intensity interval training were significantly lower than AT. Several effective exercise programs can be implemented during firefighter training academies.

Effect of High-Intensity Circuit Training versus Low-Intensity Interval Training on Functional Strength and Weight Efficacy in Overweight and Obese Young Females: A Randomized Clinical Trial

Effect of High-Intensity Circuit Training versus Low-Intensity Interval Training on Functional Strength and Weight Efficacy in Overweight and Obese Young Females: A Randomized Clinical Trial

The Effects Of High-intensity Circuit Training On Sleep And Mental Health In Female Inactive College Students

The Effects Of High-intensity Circuit Training On Sleep And Mental Health In Female Inactive College Students

Effects Of 8-week High-intensity Circuit Training On Lipid Profile And Adipokine In Sedentary Young Females

Effects Of 8-week High-intensity Circuit Training On Lipid Profile And Adipokine In Sedentary Young Females

High-intensity circuit training change serum myostatin but not myogenin in adolescents’ soccer players: a quasi-experimental study

BackgroundSkeletal muscle contractions due to exercise lead to the secretion of many proteins and proteoglycan peptides called myokines. Myostatin (MSTN) and Myogenin (MyoG) are two of the most important skeletal muscle growth regulatory factors related to myoblast differentiation and muscle hypertrophy. The present study aims at investigating the effects over eight weeks of high-intensity circuit training (HICT) on serum MyoG and MSTN in male soccer players.MethodThe present study is a quasi-experimental study on 21 male soccer players (Experimental group: n = 11, Control group: n = 10) (ages 15.0 ± 3.4 years, body mass 55.7 ± 7.8 kg, height 173.3 ± 8.0 cm, Body mass index 18.4 ± 1.9 kg m−2, maximum oxygen uptake 61.89 ± 3.01 ml kg−1 and the peak height velocity 14.5 ± 0.3 years). Participants were randomly divided into two groups: training group and a control group. The first resting blood samples were obtained in the morning-fasting state, and the second blood samples were obtained after the maximum aerobic test at pre- and post-HICT.ResultsThere were non-significant differences in resting serum values of MyoG (p = 0.309, p > 0.05) but significant differences in resting serum values of MSTN between the training and control groups after eight weeks of HICT (p = 0.003, p < 0.05). No significant differences were observed between groups in the acute response of serum values of MyoG (p = 0.413, p < 0.05) and MSTN (p = 0.465, p < 0.05) to the maximum aerobic test after eight weeks of HICT.ConclusionThese results suggest that eight weeks of HICT can decrease the resting serum values of MSTN but not change the resting serum values of MyoG in male adolescent soccer players. Also, eight weeks of HICT does not affect the acute response of MSTN and MyoG after a maximum aerobic test.

The comparative effects of periodized lower body strength training versus high intensity circuit programming in experienced runners.

The purpose of this study was to compare the effects of supplementing habitual run training with periodized lower body strength training versus high intensity circuit strength training on running performance and related variables in experienced runners. Nineteen (N.=19) participants performed 8 weeks of 2 d·wk-1 periodized lower body strength training (PLB), N.=9, or high intensity circuit training (CT), N.=10. PLB sessions included 2 sets of the back squat, standing calf raise, leg press, and dumbbell lunge, with intensity linearly periodized. CT sessions simulated CrossFit-style programming and included 2-4 heavy (>10-RM) sets of a compound lift, followed by a high intensity, whole body resistance circuit. Three-km time trial (TT), V̇O<inf>2</inf>max, relative leg press 1-RM, running economy (RE) at 2 standard submaximal velocities (SV1, SV2) between 11 and 14 km∙hr-1, RPE at SV1/SV2, and peak/mean power were assessed pre and postintervention. Similar (P≤0.02) increases occurred in RE at 11 km∙hr-1 (36.4±3.1 to 35.4±2.4 mL·kg-1·min-1) and RPE at SV1 (12.5±1.3 to 11.4±1.6). Relative 1-RM (2.54±0.41 to 3.40±0.72) and RPE at SV2 (14.1±1.3 to 12.9±1.8) improved in both groups (P≤0.03). However, PLB showed larger improvements in 1-RM (0.43±0.18 vs. 0.2±1.9, t=2.75, P=0.015) and RPE at SV2 (-1.75±0.9 vs. -0.63±1.1, t=2.30, P=0.037). TT, V̇O<inf>2</inf>max, RE at 12-14 km∙hr-1, and power were unchanged (P≥0.27). PLB and CT enhanced 1-RM, RE at 11 km∙hr-1 and RPE at SV1/SV2, but neither modality improved TT performance, V̇O<inf>2</inf>max, anaerobic power, or RE at faster velocities. PLB resulted in greater improvements in 1-RM and RPE at SV2.

Effect of a High-Intensity Circuit Training Program on the Physical Fitness of Wildland Firefighters.

Wildland firefighting implies high physical and psychological demands for the personnel involved. Therefore, good physical fitness can help increase the work efficiency of wildland firefighters (WFFs) and safeguard their health. High-intensity circuit training (HICT) could be a good alternative to improve the physical condition of WFFs since it stands out for its functionality and economy. Therefore, the objective of this study was to analyze the effects of HICT on the WFFs' physical fitness. The study involved 9 WFFs (8 males and 1 female; 29.8 ± 2.8 years; 175.6 ± 6.7 cm) who completed a training program and 9 WFF candidates (8 males and 1 female; 24.7 ± 6.6 yr, 176.5 ± 7.0 cm) as a control group. WFFs performed an 8-week HICT program (two weekly training sessions). The training sessions lasted approximately 45 min and were performed at an intensity >80% of maximal heart rate and RPE values >7.5. At the beginning and the end of the intervention, subjects' physical fitness (i.e., aerobic capacity, cardiorespiratory endurance, muscular resistance and explosive strength) was assessed through different tests. After completing the training program, WFFs had significantly increased (p < 0.05) the speed at which the ventilatory thresholds were determined (12.4 ± 13.9 and 5.7 ± 7.3% for the ventilatory and respiratory compensation thresholds, respectively) and also their abdominal (31.2 ± 17.2%), lumbar (34.1 ± 13.5%) and upper limb (13.3 ± 16.0%) strength. Moreover, improvements (p < 0.05) in the explosive strength of legs (7.1 ± 5.8%) and performance in a specific physical employment test (12.2 ± 6.1%) were observed. In conclusion, the results of this study show that an 8-week high-intensity circuit training program could be an effective and safe method to improve WFFs' physical fitness and performance.

Effect of High Intensity Circuit Training on Central Fatigue and Cognitive Function among Recreational Athletes: An Annotated Bibliographic Review

- [Purpose] Averting fatigue is an area of discussion nowadays not only for professional athletesbut also for recreational athletes. It requires comprehension about understanding of fatigue, it’s aetiology andmechanisms. (Mostafa, 2014). Central fatigue stipulates decrease in voluntary activation during exercise. Circuittraining is a type of training evolved by Morgan and Anderson in 1953. This training involves “A Circuit”including 9-12 exercises (aerobic exercises, resistance exercise etc) at nine moderate paces. It includes severalcircuits with short breaks between them. Every recreational athlete encounters fatigue in day-to-day life (Bart,2010). The type, duration and intensity of exercise are several factors which are responsible for peripheral andcentral fatigue. Total of more than 20 full text articles were included in this review. A literature search wasperformed using Google Scholar, PubMed and Cochrane databases. A total of more than 60 articles showed upon PubMed and 15 on Cochrane with the term “recreational athletes”. Exercise interventions other than highresistance circuit training were excluded. The articles were checked thoroughly and only full text articles wereincluded for this review. These studies were reviewed. This bibliographic study conclude that the circuit andhigh intensity resistance training has improved various parameters such as resistance to fatigue and cognitivefunction among recreational athletes. High Intensity Circuit Training has positive effect on cognitive functionand resistance to fatigue among recreational athletes.

Utjecaj kružnog treninga cijelog tijela na sastav tijela i kardio-respiratornu kondiciju kod odraslih osoba s prekomjernom tjelesnom težinom i sjedilačkog načina života

Obesity and low cardiorespiratory fitness are major risk factors for numerous non-communicable diseases and mortality, and efficient treatment protocols to counteract these conditions are highly warranted. We evaluated the effect of high-intensity circuit training (CIT) on body composition and cardiorespiratory fitness of sedentary overweight individuals. Cardiorespiratory and body composition were assessed before and after a 8-week circuit training (CIT; four sessions of full-body CIT per week; age, 38 ± 9 years old; height, 174 ± 10 cm; body mass, 93.1 ± 22.2 kg; n = 32), and 8-week inactiv-ity (CON; neither training nor lifestyle changes from week; 0–8 age, 39 ± 7 years old, height, 168 ± 8 cm, body mass, 89.5 ± 17.5 kg; n = 33). The two-way repeated-measures ANOVA revealed moderate to large reductions were observed in body mass, BMI, and fat percentage after CIT (d=0.43–0.81; P&amp;lt;0.05). In contrast, all body composition parameters remained stable after 8-week inactivity (P&amp;lt;0.05). A small to moderate group x moment interaction was found for body mass, BMI and % fat (d=0.10–0.60; P&amp;lt;0.05). Small improvements in VO2max were observed after CIT (d=0.48 [0.11–0.85]; P=0.010), while small to moderate reductions were observed in VO2max and PV were observed after inactivity (d=0.47 [0.11–0.83] and 0.64 [0.26–1.01], respectively; P&amp;lt;0.05). A small moment x group interaction was observed for VO2max (d= 0.19 [0.13–0.26]; P&amp;lt;0.001). Our findings suggest that 8-week of full-body circuit training may improve cardiorespiratory fitness and body composition in sedentary overweight individuals.

Effects of High-Intensity Circuit Training in Obese and Overweight Population: A Randomized Clinical Trial

Obesity is a serious risk for various cardiovascular diseases and is often managed with increased physical activity and exercise. The purpose of this study is to investigate the effects of a minimal dose, High-Intensity Circuit Training (HICT) program on a range of cardiovascular risk factors in obese and overweight individuals.

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.

Is Interval Training more Effective and Efficient Workout for Fat Loss Compared to Continuous Training?A Meta-Analysis

Background: Enhancing regular physical activity can lead to substantial health benefits. Interval-based high-intensity circuit training is an effective and efficient way of reducing body fat, yet the comparison between this type of training and long-term moderate-intensity continuous training is equivocal. Objectives: the objective was to conduct a meta-analysis for comparing high-intensity interval training with moderate-intensity continuous training on improving body fat. Method: We searched PubMed, Google Scholar, Scopus, and CINAHL for the following inclusion criteria: (a) Studies that compare high-intensity interval training and moderate-intensity continuous training using body fat as an outcome measure in a healthy population; (b) the frequency of the training at least four weeks; (c) Articles must be in the English language. Result: A total of 325 participants were included in 10 Randomized Control Trials (RCT). Results revealed that interval training has a mild pooled effect in reducing the body fat of the participants with an effect size of (SMD) of 0.26 (95% of CI=0.00 to 74.84) calculated at the random effect model. I2 14.87% (95% CI=0.01 to 0.45) in comparison to moderate-intensity continuous training performed during 6-12 weeks. Conclusion: We concluded that the intensity of effort has a significant impact in reducing fat loss in minimal time compared to continuous long-term exercise with less intensity. Keywords: Body Fat, Continuous training, Interval-Training, Sprint interval, traditional exercises

EFFECT OF HIGH INTENSITY CIRCUIT TRAINING IN PEAK EXPIRATORY FLOW RATE VALUE AMONG MALE YOUNG ADULTS

Background: Lung function has mutual correlation with exercise. Abnormal lung function can affect physical ability to exercise. Otherwise, exercise can increase lung function. Peak expiratory flow rate (PEFR) is a parameter to observe the lung function. High Intensity Circuit Training (HICT) is a combination of aerobic and endurance exercise which has total duration only 7-minutes long. High Intensity Circuit Training can be a good choice for young adults because it does not need much time, easy to be practiced, and beneficial for physical health as well. Objective: To analyze a significant increase in PEFR value after High Intensity Circuit Training for 8 weeks. Methods: This study was a quasi-experimental study with pre-test and post-test comparison group method. Samples were taken purposively from medical student of Diponegoro University (n=56, age=18-21 years old), who were divided into two groups, the control and training group. Peak flow meter was used to measure PEFR value before and after intervention. The data were analysed using Paired T test and Independent T test. Results: A significant increase of PEFR value was found after High Intensity Circuit Training for 8 weeks (p=0.000). The mean difference between pre-test and post-test PEFR value was found increased significantly (p=0.001), that training group had higher score as compared to control group. Conclusion: Regular High Intensity Circuit Training can improve lung function particularly PEFR value in male young adults.

Effects of High-Intensity Circuit Training vs. Interval Training on Body Composition and Oxygen Consumption in College Students

Objective: to identify the effects of High-Intensity Circuit Training versus Interval Training on body composition and oxygen consumption in overweight and obese young adults. Materials and Methods: quasi-experimental study. The population was made up of 106 university students, with a BMI Body Mass Index greater than 25 kg / m2. The members of the sample were randomly assigned to two groups of 15 students each: a control group (continuous training) and an experimental group (high-intensity functional training). Variables such as weight, height, body mass index, percentage of fat mass, muscle mass, bone mass, and oxygen consumption were measured. Results: the control group showed a significant decrease in body weight and BMI after the 20 training sessions; the experimental group did not show significant modifications in this variable. In relation to the percentage of body fat tissue, a statistically significant decrease in the post-test measurements was evident in the individuals of both groups. The median and interquartile ranges show better results in VO2 of the experimental group and less variability with respect to the control group in the pretest and posttest. Conclusions: High-Intensity Intermittent Training significantly reduces the percentage of body fat and oxygen consumption in people with obesity, after 20 training sessions.

Short-Term High-Intensity Circuit Training Does Not Modify Resting Heart Rate Variability in Adults during the COVID-19 Confinement.

Background/Objective: The quarantine caused by the COVID-19 pandemic increased sedentary behavior, psychological stress, and sleep disturbances in the population favoring the installation of alterations in the cardiovascular system. In this sense, physical exercise has widely been suggested as an efficient treatment to improve health. The current study determined the impact of short-term high-intensity circuit training (HICT) on resting heart rate variability (HRV) in adults. Methods: Nine healthy participants (age: 31.9 ± 4.4 yr.) performed 36 HICT sessions (3 times per day; 3 days per week) and four participants (age: 29.5 ± 1.7 yr.) were assigned to a control group. The HICT consisted of 12 min of whole-body exercises performed during a workout. Twenty-four hours before and after the exercise program, HRV parameters were recorded. Results: The heart rate exercise during the last session trended to be lower when compared with the first HICT session (p = 0.07, d = 0.39, 95% CI = −13.50, 0.72). The interval training did not modify the HRV time (Mean NN, SDNN, RMSSD, NN50, pNN50) and frequency (LF, HF, LF/HF ratio, total power) domain parameters. Conclusion: Thirty-six HICT sessions did not provide enough stimuli to modify the resting HRV in adults during social isolation elicited by the COVID-19 pandemic. However, the data suggested that exercise protocol did not induce cardio-vagal adaptations.

Body composition and physical fitness improve after 8 weeks of high-intensity circuit training using body weight in obese women.

We examined the effects of an 8-week modified high-intensity circuit training using body weight as resistance (HICTBW) on health-related physical fitness in sedentary obese women. Twenty-four sedentary obese women were allocated into the HICTBW or a non-training control group (CG). The modified HICTBW was performed for eight weeks (three times per week). Training consisted of a 30-second workout and 10-second rest for 12 exercise poses per one circuit (one circuit in the first week), with an increase of one circuit every two weeks. Body weight and body composition included skeletal muscle mass (SMM), body fat mass (BFM), body fat percentage (BF%), visceral fat area (VFA), and skeletal muscle mass to visceral fat area ratio (MFR) were measured. Physical fitness included flexibility of the lower back and hamstrings (Flex<inf>LH</inf>), and leg and handgrip muscle strength (Strength<inf>Leg</inf>, Strength<inf>HG</inf>). Cardiovascular endurance included the Åstrand-Rhyming heart rate (HR<inf>Åstrand</inf>), relative maximum oxygen uptake (relative V̇O<inf>2max</inf>), and workload. All variables were obtained at baseline, week 4, and week 8. The HICTBW improved Flex<inf>LH</inf>, Strength<inf>Leg</inf>, and relative V̇O<inf>2max</inf> from baseline to week 4 (All P<0.05). Improvements from baseline to week 8 were observed for SMM, BFM, BF%, VFA and MFR, Flex<inf>LH</inf>, Strength<inf>Leg</inf>, HR<inf>Åstrand</inf>, relative V̇O<inf>2max</inf>, and workload (All P<0.05). Furthermore, the HICTBW elicited a higher change in SMM (+2.9%), BFM (-3.4%), BF% (-3.2%), MFR (+9.5%), Flex<inf>LH</inf> (+145.7%) and relative V̇O<inf>2max</inf> (+32.3%) than the CG at week-8 (All P<0.05). An eight-week modified HICTBW program thrice a week is an effective training modality to influence health-related physical fitness in sedentary obese women.

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.

The influence of a specific high intensity circuit training during physical education classes in children’s physical activity and body composition markers

Physical activity plays a paramount role on children growth and schools emerged as a key setting for pro- moting physical activity during childhood. The aim of this study was to verify the effects of a high intensi- ty circuit training performed during regular physical education classes at schools. One hundred and five children aged 11–14 years (71 boys and 34 girls) were evaluated. The participants were split into a control group (boys: N = 47; girls: N = 16) and an experimental group (boys: N = 24; girls: N = 18). Besides the normal physical education classes, the experimental group also performed a high intensity circuit training for eight weeks, twice a week, at the beginning of the lesson. A pre- post-test was performed. Cardiorespiratory (20 m shuttle run test ) and a set of strength variables were evaluated. Percentage of fat mass was used as a somatic indicator. The 20 m shuttle run test presented a significant time effect, but not a time X sex, time X group, and time X weight status interactions. Conversely, the strength variables presented a significant time X group interaction (significant differences between groups). Percentage of fat mass presented a significant time effect, but not a significant time X group interaction. Data showed that adding a high intensity circuit training to physical education classes would result in a significant increase in muscular fitness performance in children, but cardiorespiratory fitness may not present the same magnitude of improvement. High in- tensity circuit training programs (performed during regular physical education classes at schools) seem to present a positive and significant effect in physical fitness parameters as well as reducing the percentage of fat mass.