PREDICTIVE EQUATIONS OF MAXIMUM OXYGEN CONSUMPTION BY SHUTTLE RUN TEST IN CHILDREN AND ADOLESCENTS: A SYSTEMATIC REVIEW

Combining HIIT with Small-Sided Soccer Games Enhances Cardiometabolic and Physical Fitness More Than Each Alone in Overweight Youth: A Randomized Controlled Study

This study aimed to compare the effects of a combined high-intensity interval training (HIIT) and small-sided games (SSG) training program (SSG + HIIT) with training programs consisting solely of either HIIT or SSG on the cardiometabolic and physical fitness of sedentary, overweight youth. A randomized, parallel-controlled study design was employed, with interventions lasting six weeks (twice a week, with each work time lasting 12-16 minutes). Fifty-seven sedentary, overweight male youth participants (15.1 ± 0.8 years) were assessed twice on anthropometric measures, blood pressure, endurance (using the Multi-Stage Fitness Test, MSFT), muscle power (countermovement jump and broad jump), and change of direction ability (using the 5-0-5 COD test). The session's ratings of perceived exertion (RPE) and scores on the Physical Activity Enjoyment Scale (PACES) were also monitored. The HIIT group exhibited a significantly smaller waist circumference compared to the control group (p = 0.041) after the intervention. The control group exhibited a significantly worst COD deficit compared to the SSG + HIIT (p = 0.002), SSG (p = 0.001) and HIIT (p = 0.048) after the intervention. In the case of MSFT, the group exhibited a significantly smaller distance covered than SSG + HIIT (p = 0.002), and SSG (p = 0.005). Moreover, significant differences on RPE (p < 0.001) and PACES (p < 0.001) was found between groups. The SSG + HIIT or SSG are effective for improving COD and aerobic capacity, while being more enjoyable and less intense than HIIT alone. However, HIIT is more effective in reducing waist circumference. The research limitations include the short intervention duration, lack of control for diet and external factors, and the need for longer-term research.

Daily steps, cardiorespiratory fitness, and remnant cholesterol in schoolchildren: mediation effects for cardiovascular prevention

BACKGROUND

To analyse the associations between daily steps, cardiorespiratory fitness (CRF), and remnant cholesterol in schoolchildren and to investigate whether the association between daily steps and remnant cholesterol is mediated by CRF.

METHODS

This cross-sectional study involved 394 schoolchildren (aged 9-12 years, 53.0% girls) from Cuenca, Spain. Daily steps were measured using the Xiaomi MI Band 3, CRF was assessed using the 20-m shuttle run test, and remnant cholesterol was calculated from total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol. Mean differences in CRF and remnant cholesterol by daily steps and CRF categories were tested using analysis of covariance. Mediation analysis models examined whether CRF mediates the association between daily steps and remnant cholesterol.

RESULTS

Children taking 12,000 and 9000 steps/day had higher CRF (p < 0.001) and lower remnant cholesterol (p = 0.034), respectively. Those with CRF > 47.59 kg/ml/min had lower remnant cholesterol (p = 0.009). CRF mediated the association between 1000 steps/day and remnant cholesterol (indirect effect = -0.027 (-0.055,-0.007)).

CONCLUSIONS

Both daily steps and CRF are associated with remnant cholesterol. Promoting an increase in daily steps may be a practical and promising strategy to increase CRF and, given its mediating role, to improve remnant cholesterol to prevent cardiometabolic risk in schoolchildren.

IMPACT

What's known: Remnant cholesterol is a critical indicator of cardiovascular disease risk in the early atherosclerosis. What's new: In schoolchildren, increased daily physical activity is significantly associated with higher cardiorespiratory fitness and lower remnant cholesterol, especially walking >9000 steps/day and >12,000 steps/day, respectively. What's relevant: Encouraging schoolchildren to take more daily steps may be a promising strategy to increase cardiorespiratory fitness and, given its mediating role, to improve remnant cholesterol to prevent cardiometabolic risk.

Examining the mediating role of muscle quantity in adolescents: associations with adiposity, cardiorespiratory fitness, muscular fitness, and cardiometabolic risk factors

The aim of this study was to evaluate the mediation role of muscle quantity in the relationship between physical fitness and cardiometabolic risk factors (CMRF) in adolescents. This cross-sectional study conducted with 120 adolescents of both sexes, aged between 10 and 17 years. Body mass, height, fat mass (FM), lean mass, blood pressure, high-density lipoprotein, low-density lipoprotein, triglycerides, glucose, insulin, cardiorespiratory fitness (CRF) and 1 repetition maximum strength (1-RM) with evaluation of the leg press 45° (RM-leg), bench press (RM-bench) and arm curl (RM-arm). Body mass index z-score, appendicular skeletal muscle mass, appendicular skeletal muscle mass index, lean mass index (LMI), muscle-to-fat ratio (MFR), age at peak height velocity, and CMRF z-score were calculated. The direct relation between FM and CMRF was mediated by the LMI (26%) and inverse relation between CRF and CMRF was mediated by the LMI (26%). For girls, the direct relation between FM and CMRF was mediated by the LMI (32%); the inverse relation between CRF, RM-leg, RM-arm and CMRF was mediated by the LMI (32%, 33%, and 32%, respective). For boys, the indirect effect was not significant, indicating that LMI is not a mediator in the relation between FM, CRF, 1-RM with CMRF. The direct relation between RM-leg and CMRF was mediated by the MRF (16%). This finding evidenced the importance of promoting a healthy lifestyle to improve physical fitness levels and the quantity of muscle mass in adolescents.

Effects of a 16-week recreational small-sided games soccer intervention on body composition and physical fitness in sedentary young adults: A randomized controlled study

Recreational small-sided games (SSGs) have demonstrated positive effects on body composition and physical fitness, while minimizing adverse outcomes. In this randomized controlled study, we aimed to investigate the impact of incorporating an additional 16-week intervention program involving recreational soccer SSGs on parameters related to body composition and physical fitness in sedentary young adult males and females. Sixty sedentary participants, with a mean age of 20.2 years, were randomly assigned to either the small-sided games group (SSG; n = 30) or the active control group, which participated in regular physical education classes (CG; n = 30). The SSG group engaged in the same activities as the control group but additionally participated in a recreational SSG football program. This program involved continuous and intermittent moderate-to high-intensity exercises conducted on 20 m × 30 m and 30 m × 50 m football fields. In contrast, the CG group received 1 h of physical education once a week. The interventions were administered for a duration of sixteen weeks. Baseline, 8-week, and post-intervention assessments were conducted to measure body mass (BM), body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), skinfold thickness (SFT), standing broad jump (SBJ), vertical jump (VJ), handgrip strength (HG) for both left and right hands, shuttle run distance (SRD), and shuttle run estimated VO2max. Results indicated that both male and female participants in the SSG group exhibited significant improvements in BM, BMI, SFT, WC, HC, and WHR following the intervention (p < 0.05), whereas the control group demonstrated no significant changes over the study period (p > 0.05). Additionally, SSG participants (regardless of sex) displayed significant enhancements in SBJ, VJ, HG, SRD, and VO2max (p < 0.05), while the control group did not exhibit any significant alterations (p > 0.05). The findings from this experimental study suggested that a 16-week recreational soccer SSG intervention effectively enhanced body composition and physical fitness among overweight sedentary young adults, offering a pleasurable alternative to conventional training approaches.

Influence of Maturation and Determinants of Repeated-Sprint Ability in Youth Basketball Players

ABSTRACT

Gonzalo-Skok, O, and Bishop, C. Influence of maturation and determinants of repeated-sprint ability in youth basketball players. J Strength Cond Res 38(2): 325-333, 2024-The main aims of the current study were (a) to determine the main predictors of general and specific repeated-sprint ability (RSA) tests, (b) to analyze the relationships between RSA tests and independent measures of physical performance, (c) to examine whether between-age differences exist, and (d) to assess whether maturation affects those mentioned above in young basketball players. Thirty-five young (U-14 to U-16), highly trained basketball players performed a linear sprint test (5, 10, and 25 m), an incremental running test, and 2 repeated-sprint tests (general [RSG]: 6 × 25 m; specific [RSS]: 6 × 5 + 5 m with a 45° change of direction and 20 seconds of passive recovery in both tests). Anthropometric variables were measured and used to calculate age at peak height velocity (APHV), which was used to determine maturation. The main determinants of RSA tests were aerobic performance and linear sprinting for RSS ( R2 = 0.84) and adding the percentage of body fat for RSG ( R2 = 0.94). Almost perfect relationships ( r = 0.93-0.99) were found between all RSA variables (i.e., the best [RSG b and RSS b ] and mean time [RSG m and RSS m ]). As age increased, performance in RSA was evident, as shown by improved best and mean scores. When APHV was controlled for, no significant differences were apparent in the comparison from U-14 and U-16 in 25 m, RSG b , and RSG m . By contrast, significant differences ( p < 0.05) were still evident with APHV controlled between U-14 and U-16 in 5 m, 10 m, RSS b , and RSS m . In conclusion, maturation positively affects linear sprinting and linear RSA performance, whereas specific (multidirectional) RSA seems to be related to other factors.

Which indices of cardiorespiratory fitness are more strongly associated with brain health in children with overweight/obesity?

PURPOSE

To compare the strength of associations between different indices of cardiorespiratory fitness (CRF) and brain health outcomes in children with overweight/obesity.

METHODS

Participants were 100 children aged 8-11 years. CRF was assessed using treadmill exercise test (peak oxygen uptake [V̇O2peak ], treadmill time, and V̇O2 at ventilatory threshold) and 20-metre shuttle run test (20mSRT, laps, running speed, estimated V̇O2peak using the equations by Léger et al., Mahar et al., and Matsuzaka et al.). Intelligence, executive functions, and academic performance were assessed using validated methods. Total gray matter and hippocampal volumes were assessed using structural MRI.

RESULTS

V̇O2peak /body mass (β = 0.18, 95% CI = 0.01-0.35) and treadmill time (β = 0.18-0.21, 95% CI = 0.01-0.39) were positively associated with gray matter volume. 20mSRT laps were positively associated with executive functions (β = 0.255, 95% CI = 0.089-0.421) and academic performance (β = 0.199-0.255, 95% CI = 0.006-0.421), and the running speed was positively associated with executive functions (β = 0.203, 95% CI = 0.039-0.367). Estimated V̇O2peak/Léger et al. was positively associated with intelligence, executive functions, academic performance, and gray matter volume (β = 0.205-0.282, 95% CI = 0.013-0.500). Estimated V̇O2peak/Mahar et al. and V̇O2peak/Matsuzaka et al. (speed) were positively associated with executive functions (β = 0.204-0.256, 95% CI = 0.031-0.436).

CONCLUSION

Although V̇O2peak is considered the gold standard indicator of CRF in children, peak performance (laps or running speed) and estimated V̇O2peak/Léger et al. derived from 20mSRT had stronger and more consistent associations with brain health outcomes than other indices of CRF in children with overweight/obesity.

Physical Fitness Responses after Sixteen Weeks of Three Fitness Program Trainings in Untrained Subjects

The remarkable popularity of fitness trends like high intensity functional training (HIFT), choreographed high intensity classes (CHIC) and resistance (RT) trainings raises the question on their effect on cardio-respiratory, lactate removal rate, endurance and body composition responses. The purpose of this study was to assess and compare these effects. Ninety-five participants were randomly assigned into 16 weeks of these trainings, five sessions/week. Anthropometric and fitness tests were carried out before training (PRE), after eight (8W) and sixteen weeks (16W). Body composition measures demonstrated significant decrease in body fat percentage (p<0.001, d=0.17-0.54) for all groups and fat mass (p< 0.001, d= 0.26-0.53) for HIFT and CHIC in 8W,16W and in 16W for RT (p= 0.03, d= 0.14), also significant increase in fat free mass only in HIFT (p< 0.002, d= 0.06-0.21) and RT (p< 0.001, d= 0.17-0.33) in 8W,16W. Cardio-respiratory measures demonstrated significant improvements in maximal aerobic capacity for HIFT (p< 0.001, d= 0.58-1.26) and CHIC (p< 0.001, d= 0.45-1.21) in 8W,16W. Endurance tests demonstrated significant improvements in 8W,16W in aerobic endurance among HIFT (p< 0.001, d= 1.28-3.19) and CHIC (p< 0.001, d= 1.16-1.79), in muscle absolute endurance in three groups (p< 0.002, d= 0.14-1.17)and muscle relative endurance in HIFT (p< 0.02, d= 0.13-0.2)and RT (p= 0.03, d= 0.3) in 16W. We can conclude that HIFT and CHIC are effective for cardio-respiratory and endurance improvement and all three programs are effective in reducing body fat.

The Multistage 20-m Shuttle Run Test for Predicting VO2Peak in 6-9-Year-Old Children: A Comparison with VO2Peak Predictive Equations

This study aimed (i) to verify if using and carrying a portable gas analyzer (PGA) constrained the performance of school children on the multistage 20-m shuttle run test (20mSRT), (ii) to verify which peak oxygen consumption (VO2peak) predictive equations have greater agreement with VO2peak values measured by direct oximetry using the 20mSRT. The study participants were 130 children ((67 boys (age 7.76 ± 0.97 years) and 63 girls (age 7.59 ± 0.91 years)), who performed two randomized trials of the 20mSRT with and without a PGA. Twenty-two predictive equations predicted the VO2peak values through the performance of the test with and without a PGA. Without a PGA, lower values of maximal speed (MS), total laps (TL), and total time (TT) were found for girls than for boys with a PGA. Only six equations were considered to correctly predict VO2peak. In general, higher MS, TL, and TT values were found with the use of a PGA. The predicted VO2peak values from the 20mSRT varied significantly among the published predictive equations. Therefore, we suggest that the six equations that presented satisfactory accuracy could be practically used to examine cardiorespiratory fitness in schools and in research with large populations when direct measurement of VO2peak is not feasible.

Adiposity Mediates the Association of Objectively Measured Physical Activity with Cardiorespiratory Fitness in Children

Background: The relationship of physical activity (PA) to cardiorespiratory fitness (CRF) is well established in children. However, the extent to which adiposity affects this association remains unclear. Objective: The study aimed to explore whether the relationships of different PA intensities to CRF are explained by adiposity. Methods: Cross-sectional data were collected from 374 children (51.87% boys) aged 7-12 years. The time spent (min/day) in vigorous PA (VPA), moderate PA (MPA), light PA (LPA), and sedentary behavior was objectively measured using triaxial accelerometry. Height, weight, and waist circumference (WC) were objectively measured, from which the BMI was derived. The 20-meter shuttle run test was conducted to estimate maximal oxygen consumption [VO_2max, mL/(kg·min)]. Linear mixed models and mediation analysis with bootstrapping were used to analyze data. Results: VO_2max was positively associated with VPA [β = 0.143, 95% confidence interval (95% CI): 0.091 to 0.194], MPA (β = 0.051, 95% CI: 0.016 to 0.086), and moderate-to-vigorous PA (MVPA) (β = 0.052, 95% CI: 0.029 to 0.075), but not LPA or sedentary time. Both BMI and WC partially mediated the relationships of VPA and MVPA to VO_2max, with the percentage of the total effect mediated by adiposity ranging from 18.0% to 19.6%. Similar results were also observed among boys but not among girls. Conclusions: Only moderate or vigorous intensity of PA is favorably correlated with CRF in children. BMI and WC play a pivotal mediating role in these associations, especially in boys, suggesting that promoting higher intensity of PA might benefit children's CRF through reducing adiposity.

Validation of equations to estimate the peak oxygen uptake in adolescents from 20 metres shuttle run test

This study aimed to develop new prediction models from directly determined peak of oxygen uptake (VO_2peak) in adolescents using 20-metre shuttle run test (20 m-SR) and to compare the new models with previously published equations. This study included 148 adolescents (43% girls), aged 13.37 ± 1.84 years old. Adolescents were randomly assigned to validation (n = 91) and cross-validation (n = 57) groups. VO_2peak was measured using a gas analyser in both maximal exercise tests in the laboratory as well as by 20 m-SR. The multiple linear regression method was applied to develop the models using BMI, BMI-z score and body fat percentage (%FM). The proposed models presented better predictive performance (R2 = 75.6% to 78.9%) and a lower absolute percentage error (%error = 10.51 to 11.78%) than the previously published equations (R2 = 38.8% to 69.1%; %error = 13.13% to 21.54%). The Model with BMI-z was the best fit equation in girls, and the model with BMI-z and %FM in boys. Therefore, it is recommended that the equations developed in the present study be used in future research and projects in the school environment to estimate VO_2peak in adolescents by the 20 m-SR test.

Heart rate agreement between the 20-meter shuttle run test and virtual system in healthy children: a cross-sectional study

BACKGROUND

Earlier studies evaluated the physiological responses to video games in children with different clinical conditions; however, no study has compared active video games with an incremental field test in healthy children. The purpose of this study was to verify the agreement between the 20-m shuttle run test (20 m-SRT) and virtual system (VS).

METHODS

This is a cross-sectional study of 235 children (9.0 ± 0.8 years, 109 boys). The two tests were performed one week apart and the children were instructed not to engage in any physical exercise or sports in the 24 h preceding each test. Their resting heart rate was monitored for one minute and then throughout the tests. To evaluate the influence of motivation on the 20 m SRT and (VS), at the end of the tests the children were asked to rate their motivation on a scale of zero to 10, zero being "not cool" and 10 "awesome". Perceived exertion at the end of the tests was assessed using the modified Borg scale.

RESULTS

Maximum heart rate (HRmax) did not differ between the 20 m-SRT and VS (194.4 ± 10.2 bpm vs. 193.2 ± 13.8 bpm, respectively). Both tests were similar for intensity > and < 96% HRmax. The children showed greater exertion on the Borg scale and motivation during the VS. The multiple logistic regression model showed that motivation (p = 0.98), sex (p = 0.53), age (p = 0.61), nutritional status (p = 0.65), and speed (p = 0.18) were not predictive factors of the child's reaching HRmax.

CONCLUSION

VS can be used as a tool to evaluate the intensity of maximal exercise tests, given that the percentage of children who achieved HRmax did not differ between the VS and 20 m SRT. The perceived exertion scales were correlated, but only the modified Borg scale correlated with HRmax in the 20 m SRT. The tests are motivational, and most children obtained the maximum VS score.