Sequencing Effects of Concurrent Strength and Endurance Training on Selected Measures of Physical Fitness in Young Male Soccer Players: A Randomized Matched-Pairs Trial

BACKGROUND

Various physical fitness qualities such as muscle strength, speed and endurance are related to soccer performance. Accordingly, the combination of strength and endurance training (i.e., concurrent training [CT]) is an often-encountered training regimen in soccer. Less is known about the effects of CT sequencing on performance in young soccer players. The aim of this study was to assess the sequencing effects of strength and intermittent endurance training applied within the same training session (intrasession) on measures of physical fitness and soccer performance in young soccer players.

METHODS

Fifty male adolescent soccer players volunteered to participate in this study which was conducted in the Netherlands in 2019. Players were randomly assigned to a strength-endurance (SE) or an endurance-strength (ES) group in matched pairs based on their countermovement jump (CMJ) performance at baseline. Both groups completed a 12-weeks in-season training program with two weekly CT sessions. Training sessions consisted of 15 min plyometric exercises and 15 min soccer-specific intermittent endurance training. Both groups performed the same training volumes and the only difference between the groups was the CT intrasession sequencing scheme (SE vs. ES). Pre and post intervention, proxies of muscle power (CMJ, squat jump [SJ]), linear sprint speed (30-m sprint test), agility (Illinois test with / without ball), and soccer performance (ball kicking velocity) were tested.

RESULTS

Data from 38 players aged 14.8 ± 1.0 years (body height 172.9 ± 8.1 cm, body mass: 57.0 ± 7.2 kg, soccer experience: 8.8 ± 2.8 years, age from peak-height-velocity [PHV]: +1.2 ± 1.0 years) were included. Significant main time effects were found for CMJ (p = 0.002, d = 0.55), SJ (p = 0.004, d = 0.51), the Illinois agility test with ball (p = 0.016, d = 0.51), and ball kicking velocity (p = 0.016, d = 0.51). Significant group-by-time interactions were observed for 30-m linear sprint speed (p < 0.001, d = 0.76) with ES showing greater improvements (p = 0.006, d = 0.85, Δ-5%).

CONCLUSIONS

Both CT-sequencing types improved performance in the tests administered. The intrasession CT sequencing (SE vs. ES) appears not to have a major impact on physical fitness adaptations, except for linear sprint speed which was in favor of ES.

Relationship between rest-activity rhythms and cardiorespiratory fitness in middle-aged workers: a cross-sectional study with non-parametric analysis using accelerometers worn on the thigh

BACKGROUND

Rest-activity rhythms are directly related to health risks, but there are limited objective methods to assess them. This study aimed to investigate the relationship between rest-activity rhythms and cardiorespiratory fitness (CRF) in middle-aged workers.

METHODS

Peak oxygen uptake was measured on a treadmill to assess CRF in 254 middle-aged workers who were divided into low, medium, and high-CRF groups based on tertiles. Participants were asked to wear an accelerometer (activPAL) on their thighs for 1 week, and the logarithmically transformed acceleration data were used for the analysis of a 24-hour rest-activity rhythm. Sex, age, body mass index, occupation, smoking status, and alcohol consumption were used as covariates in Model 1, with Model 2 also including walking count on non-workdays. Repeated measures analysis of variance was used to compare time course of rest-activity rhythms changes on workdays between groups, and post-hoc tests were conducted using Bonferroni's correlation.

RESULTS

Higher CRF correlated with increased physical activity. In model 1, higher CRF showed improved interdaily stability, but the significant difference disappeared in model 2 after adjusting for non-workday walking counts. A time-course group comparison showed that the high group had significantly higher activity levels than those of the low group from 6:00 to 8:59 and 17:00 to 17:59 and the medium group from 6:00 to 7:59 and 19:00 to 19:59.

CONCLUSIONS

Workers who have better rest-activity rhythms and engage in higher levels of physical activity on workdays tend to have higher CRF levels. Regular daily routines, influenced by physical activity during holidays, can positively impact cardiopulmonary endurance.

Independent and joint associations of cardiorespiratory fitness and BMI with dementia risk: the Cooper Center Longitudinal Study

OBJECTIVE

This study aimed to examine the association of midlife fitness and body mass index (BMI) with incident dementia later in life.

DESIGN AND PARTICIPANTS

A cohort study of 6428 individuals (mean age 50.9±7.6 years) from the Cooper Center Longitudinal Study.

MEASURES

Cardiorespiratory fitness and BMI were assessed twice (1970-1999) during visits to the Cooper Clinic, a preventive medicine clinic in Dallas, Texas. These measures were examined as continuous and categorical variables. As continuous variables, fitness and BMI were examined at baseline (averaged of two examinations) and as absolute change between exams (mean time 2.1±1.8 years). Variables were categorised: unfit versus fit and normal versus overweight/obese. Medicare claims data were used to obtain all-cause dementia incidence (1999-2009). Mean follow-up between midlife examinations and Medicare surveillance was 15.7 ((SD=6.2) years. Multivariable models were used to assess the associations between fitness, BMI and dementia.

RESULTS

During 40 773 person years of Medicare surveillance, 632 cases of dementia were identified. After controlling for BMI and covariates, each 1-metabolic equivalent increment in fitness was associated with 5% lower (HR 0.95; 95% CI 0.90 to 0.99) dementia risk. In comparison, after controlling for fitness and covariates, each 1 kg/m2 increment in BMI was associated with a 3.0% (HR 1.03; 95% CI 1.00 to 1.07) higher risk for dementia, yet without significance (p=0.051). Similar findings were observed when the exposures were categorised. Changes in fitness and BMI between examinations were not related to dementia. Jointly, participants who were unfit and overweight/obese had the highest (HR 2.28 95% CI 1.57 to 3.32) dementia risk compared with their fit and normal weight counterparts.

CONCLUSION

Lower midlife fitness is a risk marker for dementia irrespective of weight status. Being unfit coupled with overweight/obese status might increase one's risk for dementia even further.

How little is enough? The feasibility of conducting a dose-escalation study for exercise training in people with stroke

QUESTION

Is it feasible and safe to conduct an exercise dose-finding study in people with stroke? Is it possible to determine a minimal dose of exercise required to see clinically meaningful improvements in cardiorespiratory fitness?

METHODS

Dose-escalation study. Twenty people with stroke (n=5 per cohort) who were able to walk independently participated in home-based, telehealth-supervised aerobic exercise sessions 3 d/week at moderate-vigorous intensity for 8 weeks. Dose parameters of frequency (3 d/week), intensity (55-85% of heart rate peak) and program length (8 weeks) were kept constant. The duration of exercise sessions was increased by 5 min per session from Dose 1 (10 min/session) to Dose 4 (25 min/session). Doses were escalated if safe and tolerable (< 33% of a cohort reaching a dose-limiting threshold). Doses were efficacious if ≥ 67% of a cohort increased peak oxygen consumption ≥ 2mL/kg/min.

RESULTS

Target exercise doses were well adhered to, and the intervention was safe (480 exercise sessions delivered; one fall resulting in minor laceration) and tolerable (no participants met the dose-limiting threshold). None of the exercise doses met our criterion for efficacy.

CONCLUSIONS

It is possible to conduct a dose-escalation trial for people with stroke. The small cohort sizes may have limited the ability to determine an efficacious minimum dose of exercise. Providing supervised exercise session at these prescribed doses via telehealth was safe.

REGISTRATION

The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12617000460303).

Korean vs. Western Exercise Capacity Nomograms for Korean Patients With Cardiovascular Disease

BACKGROUND

Exercise capacity is known to be an independent predictor of cardiovascular events and mortality. However, most previous studies were based on Western populations. Further study is warranted for Asian patients according to ethnic or national standards. We aimed to compare prognostic values of Korean and Western nomograms for exercise capacity in Korean patients with cardiovascular disease (CVD).

METHODS

In this retrospective cohort study, we enrolled 1,178 patients (62 ± 11 years; 78% male) between June 2015 and May 2020, who were referred for cardiopulmonary exercise testing in our cardiac rehabilitation program. The median follow-up period was 1.6 years. Exercise capacity was measured in metabolic equivalents by direct gas exchange method during the treadmill test. The nomogram for exercise capacity from healthy Korean individuals and a previous landmark Western study was used to determine the percentage of predicted exercise capacity. The primary endpoint was the composite of major adverse cardiovascular events (MACE; all-cause death, myocardial infarction, repeat revascularization, stroke and hospitalization for heart failure).

RESULTS

A multivariate analysis showed that the risk of primary endpoint was more than double (hazard ratio [HR], 2.20; 95% confidence interval [CI], 1.10-4.40) in the patients with lower exercise capacity (< 85% of predicted) by Korean nomogram. The lower exercise capacity was one of the strong independent predictors along with left ventricular ejection fraction, age, and level of hemoglobin. However, the lower exercise capacity by Western nomogram could not predict the primary endpoint (HR, 1.33; 95% CI, 0.85-2.10).

CONCLUSION

Korean patients with CVD with lower exercise capacity have higher risk of MACE. Considering inter-ethnic differences in cardiorespiratory fitness, the Korean nomogram provides more suitable reference values than the Western nomogram to determine lower exercise capacity and predict cardiovascular events in Korean patients with CVD.

Influence of physical fitness of coronary disease patients on vagal reentry and heart rate recovery after exercise with and without fluid replacement

BACKGROUND

Fluid replacement during exercise has been studied as an important strategy to enhance recovery, however, studies are needed to investigate the effect of this strategy in different physical profiles. The aim of the study was to investigate the influence of physical fitness of coronary artery disease (CAD) patients on vagal reentry and heart rate recovery after exercise performed with and without fluid replacement.

METHODS

Non-randomized crossover clinical trial. 33 CAD patients were submitted to: I. cardiopulmonary exercise test: to divide the sample into lower and higher VO₂ peak groups; II. Control Protocol (CP): composed of rest, aerobic exercise and passive recovery; III. Hydration Protocol (HP): composed of the same activities as the CP, but with water intake during exercise. The recovery was evaluated by vagal reentry and heart rate recovery immediately after exercise.

RESULTS

The results did not show significant differences between the higher and lower VO₂ peak groups. In addition, the hydration strategy adopted was not able to cause significant changes between control and hydration protocols, regardless of group. However, a time effect was observed, suggesting anticipation of vagal reactivation and heart rate reduction in hydration protocol.

CONCLUSIONS

Physical fitness did not influence vagal reentry and heart rate recovery in CAD patients after exercise. However, the hydration strategy seems to have anticipated vagal reentry and produced a more efficient reduction in heart rate regardless of the individuals' physical fitness, but these results should be analyzed with caution due to the absence of significant differences between groups and protocols. This article is protected by copyright. All rights reserved.

Construct validity and reliability of the 2-Minute Step Test (2MST) in individuals with low back pain

BACKGROUND

Functional tests are important clinical tools, since they are non-invasive methods, with simple applicability, and low cost. However, there are few tests adapted for individuals with chronic low back pain. Thus, our objective was to evaluate the test-retest and inter-rater reliability of the 2-Minute Step Test in individuals with chronic low back pain and to correlate the test score with measures of pain and physical activity.

METHODS

We included patients aged between 18 and 45 years, of both sexes, and with low back pain. The interval between the test and retest was 7 days. We analyzed the data via intra-class correlation coefficient (ICC), confidence interval at 95%, standard error of measurement, and minimum detectable change for reliability. We used the Spearman's correlation coefficient to verify the correlation between 2-Minute Step Test and measures of pain and physical activity (Numerical Pain Scale, Roland-Morris Disability Questionnaire, Pain-Related Catastrophizing Thoughts Scale, Tampa Scale of Kinesiophobia, and Baecke Habitual Physical Activity Questionnaire).

RESULTS

Sample is composed of 37 individuals, most of them female, with overweight and low back pain > 60 months. 2-Minute Step Test showed excellent test-retest (ICC = 0.903) and inter-rater (ICC = 0.925) reliability. Sport domain of the Baecke showed a significant correlation with the 2-Minute Step Test (rho = 0.444).

CONCLUSION

2-Minute Step Test is a reliable measure to measure the functional capacity of patients with chronic low back pain considering different times and examiners, as well as being positively correlated with sports practice.

Title: Assessment of VO2peak and Exercise Capacity after Stroke: a Validity Study of the Human Activity Profile Questionnaire

OBJECTIVE

to investigate, in individuals after stroke, the concurrent validity of the Human Activity Profile (HAP) to provide the VO_2peak and the construct validity of the HAP to assess exercise capacity; and to provide equations based upon the HAP outcomes to estimate the distance covered in the Incremental Shuttle Walking Test (ISWT).

DESIGN

Cross-sectional study.

SETTING

University laboratory.

PARTICIPANTS

Fifty-seven individuals (54±11 years) after stroke.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

Agreement between the VO_2peak provided by the HAP (lifestyle energy consumption (LEC) outcome, in mL.kg^-1.min^-1) and the gold standard measure of the VO_2peak (mL.kg^-1.min^-1), obtained through the symptom-limited Cardiopulmonary Exercise Test (CPET). Correlation between the HAP outcomes (LEC; the maximum activity score (MAS) and the adjusted activity score (AAS)) and the construct measure: the distance covered (in meters) in the ISWT. An equation to estimate the distance covered in the ISWT was determined.

RESULTS

High magnitude agreement was found between the VO_2peak, in mL.kg^-1.min^-1, obtained by the symptom-limited CPET and the value of VO_2peak, in mL.kg^-1.min^-1, provided by the HAP (LEC) (ICC=0.75;p<0.001). Low to moderate magnitude correlations were found between the distance covered in the ISWT and the HAP (LEC/MAS/AAS) (0.34≤rho≤0.58). The equation to estimate the distance covered in the ISWT explained 31% of the variability of the ISWT (ISWT_estimated=-361.91+(9.646xAAS)).

CONCLUSION

The HAP questionnaire is a clinically applicable way to provide a valid value of VO_2peak (in mL.kg^-1.min^-1) and to assess the exercise capacity of individuals after stroke. Furthermore, an equation to estimate the distance covered in the submaximal field exercise test (ISWT) based on the result of the AAS (in points) was provided.

Evaluation of cardiopulmonary system outcomes in children with developmental coordination disorder: A systematic review

BACKGROUND

children with Developmental Coordination Disorder (DCD) tend to avoid physical activity, which can affect their health and well-being.

AIM

Conduct a systematic review to identify, synthesize and compile data from the literature on the evaluation of the cardiopulmonary system in children with DCD.

METHOD

According to PRISMA guidelines, we searched for articles indexed in PubMed, LILACS, Scopus, Web of Science, and Cochrane Library. The strategy was directed at the Population (children), Exposure (DCD), Outcomes (descriptors related to cardiopulmonary evaluation).

RESULTS

A total of 59 articles were identified through the databases. In the end, after analyzing the titles, abstracts, and full articles, including articles through manual search in the lists of bibliographic references, 13 articles relevant to the topic were included. All selected studies evaluated cardiorespiratory fitness / aerobic capacity parameters, and only three studies included the assessment of lung function.

CONCLUSION

Although very heterogeneous, the evidence found in this review suggests that children with DCD have less cardiorespiratory fitness and lower lung function when compared to children with typical development. However, new studies are suggested to investigate and strengthen the evidence found in the present study.

Feasibility and effects of high-intensity interval training in older adults living with HIV

Adults with HIV on therapy can live a normal lifespan but exhibit advanced ageing which includes reduced cardiorespiratory fitness. Our objective was to determine the feasibility and effects of high-intensity interval training (HIIT) combined with resistance training (RT) in older adults with HIV. We conducted a cross-over pilot study within a randomized exercise trial in sedentary adults with HIV ≥50 years of age. First, participants were randomized to 4 months of continuous high-intensity aerobic exercise (AEX) and RT 3x/week or standard of care control. Then, the control group completed 4 months of HIIT + RT (3x/week). Among the 32 individuals enrolled, 26 eligible participants were randomized. Most participants were African American (63%) and male (95%) with a mean (SD) age of 61.5 (6.7) years and VO₂peak of 24.5 (4.9) ml/kg/min. Attendance and adherence to both exercise training interventions were high. The clinically significant increases in VO₂peak (ml/kg/min) after HIIT (3.09 ±1.04, p=0.02) and AEX (2.09 ±0.72, p=0.01) represented improvements of 17.1% and 7.7%, respectively. Both groups had improvements in exercise endurance (time on the treadmill) and strength (all p< 0.01). This pilot study supports HIIT as an efficient means to deliver high-intensity AEX to improve cardiorespiratory fitness toward the goal of attenuating the accelerated ageing process in adults with HIV.

Association between Physical Fitness and Cardiometabolic Risk of Children and Adolescents in Korea

Background

This study aimed to investigate the association between physical fitness and cardiometabolic health of Korean children and adolescents.

Methods

In total, 168 participants (89 boys and 79 girls) aged 10–16 years were recruited for the Intervention for Childhood and Adolescent Obesity via Activity and Nutrition Study in 2016. The subjects were categorized into two groups using the definition of metabolic syndrome by the International Diabetes Federation: metabolically unhealthy (with at least two of the five criteria) and healthy groups (with less than one criterion). Correlation analysis of the participants’ general characteristics was performed. Odds ratios (ORs) of physical fitness for cardiometabolic risk were evaluated via logistic regression.

Results

Metabolically unhealthy children showed greater weight, height, and body mass index, higher Children’s Depression Inventory score, and longer screen time than did the metabolically healthy children. Metabolically healthy children showed greater upper and lower extremity muscular strength than did the metabolically unhealthy children (P=0.04 and P<0.001, respectively). In the multiple logistic regression analysis, lower extremity muscle strength was inversely related to the clustered cardiometabolic risk of the children and adolescents with or without adjustment for confounders (OR, 4.32; 95% confidence interval [CI], 1.87–9.97; OR, 7.64; 95% CI, 1.55– 37.74, respectively).

Conclusion

Physical fitness, especially lower extremity muscle strength, is significantly inversely associated with individual and clustered cardiometabolic risks in Korean children and adolescents.

Socioeconomic Correlates and Determinants of Cardiorespiratory Fitness in the General Adult Population: a Systematic Review and Meta-Analysis

BACKGROUND

This review aims to (1) consolidate evidence regarding the association between socioeconomic status (SES) and cardiorespiratory fitness (CRF), (2) conduct a meta-analysis of the association between SES and CRF using methodologically comparable data, stratified by sex, and (3) test whether the association varies after adjustment for physical activity (PA).

METHODS

A systematic review of studies from MEDLINE, EMBASE, Latin American and Caribbean Health Sciences (LILACS), Scientific Electronic Library Online (ScIELO), and Cochrane Library without time or language restrictions, which investigated associations between SES and CRF. Risk of bias within studies was assessed using a customized quality assessment tool. Results were summarized in table format and methodologically similar studies were synthesized using meta-analysis of Hedges' g effect sizes. Synthesized results were appraised for cross-study bias. Results were tested for the impact of PA adjustment using meta-regression.

RESULTS

Compared to individuals with low education, both men and women showed higher CRF among individuals with high education (men 0.12 [0.04-0.20], women 0.19 [0.02-0.36]), while participants with medium education showed no significant difference in CRF (men 0.03 [- 0.04-0.11], women 0.09 [- 0.03-0.21]). Adjustment for PA did not significantly impact the association between education and CRF.

CONCLUSIONS

There is fair evidence for an association between high levels of education and increased CRF. This could have implications for monitoring, of health target compliance and of chronic disease risk among higher risk populations, to detect and prevent non-communicable diseases (NCDs) and to diminish social health inequalities.

TRIAL REGISTRATION

PROSPERO, CRD42017055456.

Unobtrusive Estimation of Cardiorespiratory Fitness with Daily Activity in Healthy Young Men

Despite the importance of cardiorespiratory fitness, no practical method exists to estimate maximal oxygen consumption (VO₂max) without a specific exercise protocol. We developed an estimation model of VO₂max, using maximal activity energy expenditure (aEEmax) as a new feature to represent the level of physical activity. Electrocardiogram (ECG) and acceleration data were recorded for 4 days in 24 healthy young men, and reference VO₂max levels were measured using the maximal exercise test. aEE was calculated using the measured acceleration data and body weight, while heart rate (HR) was extracted from the ECG signal. aEEmax was obtained using linear regression, with aEE and HR as input parameters. The VO₂max was estimated from the aEEmax using multiple linear regression modeling in the training group (n = 16) and was verified in the test group (n = 8). High correlations between the estimated VO₂max and the measured VO₂max were identified in both groups, with a 15-hour recording being sufficient to produce a highly accurate VO₂max estimate. Additional recording time did not significantly improve the accuracy of the estimation. Our VO₂max estimation method provides a robust alternative to traditional approaches while only requiring minimal data acquisition time in daily life.

Autonomic function change following a supervised exercise program in patients with congestive heart failure

BACKGROUND

Few studies have investigated changes in autonomic function after training in patients with cardiovascular diseases, particularly patients with congestive heart failure (CHF). Heart rate recovery (HRR) is a strong predictor of mortality in coronary artery disease (CAD) patients. The aim of this study was to determine the effect of 8 weeks of supervised exercise training on autonomic function, which were assessed by heart rate, systolic blood pressure (SBP), and rate-pressure product (RPP) in CHF patients.

METHODS

65 patients aged 57-82 years with CHF were assigned to two groups randomly. The first group received a supervised 8-week aerobic training program of 30-45 min sessions, 3 days per week on alternate days, while controls received standard medical care and were followed up. Body weight, body mass index, functional capacity, resting heart rate, HRR, resting systolic blood pressure, peak heart rate, peak systolic blood pressure, and RPP were measured before and after the study period. Medications and diet recommendations remained unchanged in both groups during the study period.

RESULTS

The exercise group consisted of 33 patients with mean age of 61.54 ± 5.89 years and the controls were 32 patients with mean age of 60.94 ± 5.03 years. One-way analysis of variance (ANOVA) with repeated measures revealed a statistically significant difference in the exercise group compared to the control group regarding body mass index, resting heart rate, heart rate recover, functional capacity, peak heart rate, peak systolic blood pressure, peak RPP after 8 weeks (P ≤ 0.05).

CONCLUSION

In conclusion, a multidisciplinary CR program with supervised exercise training support significantly improves functional capacity and autonomic function in CHF patients. Therefore, a supervised and guided exercise training program is safe and beneficial for patients with CHF with different etiologies.

Effects of a 6-Month Walking Study on Blood Pressure and Cardiorespiratory Fitness in U.S. and Swedish Adults: ASUKI Step Study

Purpose

The aim of this study was to assess the effects of a six-month pedometer-based workplace intervention on changes in resting blood pressure (BP) and cardiorespiratory fitness (CRF).

Methods

A subsample of ASUKI Step participants (n= 355) were randomly selected to have changes in their BP and CRF monitored during the intervention. Pedometers were used to monitor steps taken with a goal of walking more than 10,000 steps/day. Systolic and diastolic BP were taken using an Omron automated BP cuff. Estimated VO₂ max was obtained using the Åstrand-Rhyming cycle ergometer test. A multi-level growth modeling approach, and a mixed model ANOVA were used to predict changes in systolic and diastolic BP, and estimated VO₂ max over time by steps, age, gender, and university site.

Results

Steps/day averaged 12,256 (SD = 3,180) during month 1 and steadily decreased to month 6. There were significant linear and quadratic trends in systolic and diastolic BP over time. Age was positively related to initial starting values for systolic and diastolic BP, and approached significance for systolic BP changes over time. Steps/day approached significance for linear changes in systolic BP. There was a significant difference between ASU and KI participants’ estimated VO₂ max. There was a significant change over time in the estimated VO₂ max. The number of steps taken was significantly related to changes in estimated VO₂ max over time.

Conclusions

The results of the present study indicate that healthy individuals who took part in a pedometer intervention improved several cardiovascular disease risk factors.