Are fixed-rate step tests medically safe for assessing physical fitness?

StepTest4all: Improving the Prediction of Cardiovascular Capacity Assessment in Young Adults

Cardiovascular capacity, expressed as maximal oxygen uptake (VO2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The aim of this study was to investigate the influence of the physical activity levels (PAlevel) of participants in the StepTest4all (validated protocol for the estimation of VO2max in adults). The sample consisted of 69 participants, including 27 women (age 21.7 ± 3.6 years; body mass = 63.5 ± 14.8 kg; height = 1.64 ± 0.06 m; body mass index = 23.7 ± 5.3 kg/m2) and 42 men (aged 21.7 ± 3.4 years; body mass = 72.0 ± 7.3 kg; height = 1.77 ± 0.07 m; body mass index = 23.1 ± 2.1 kg/m2). The participants were assigned to one of the two groups: (i) the VO2max prediction group and (ii) the prediction model validation group. In the multiple linear regression, the following predictors of VO2max remained significant: sex (p < 0.001), physical activity level (p = 0.014), and HRR60 (p = 0.020). The prediction equation (R2 = 74.0%, SEE = 4.78) showed a close and strong relationship between the measurements and can be expressed as follows: VO2max = 17.105 + 0.260·(HRR60) + 8.563·(sex) + 4.097·(PAlevel), in which HRR60 is the magnitude of the HR decrease (bpm) in one minute immediately after stopping the step, and sex: men = 1, women = 0, and PAlevel is level 1 (low), level 2 (moderate), and level 3 (high). The StepTest4all was shown to be a suitable method for estimating cardiovascular capacity, expressed as VO2max, in young adults. Retaining PAlevel as a significant predictor allows us to better individualize the participants' VO2max.

Effects of Aerobic Exercise Combined With Attentional Bias Modification in the Care of Male Patients With a Methamphetamine Use Disorder

OBJECTIVE

It remains unclear which individual or combined strategies are most beneficial for methamphetamine use disorders (MUDs). We compared the effects of aerobic exercise, attentional bias modification, and combined intervention on male patients with MUD.

METHOD

One hundred male patients with MUD were randomly assigned to combined intervention, aerobic exercise, attentional bias modification, or control groups (25 patients per group). The 8-week intervention protocol included three 60-minute sessions of aerobic exercises per week. Primary outcomes included high- and low-frequency heart rate variability, executive function, and cardiorespiratory fitness measured by customized software, computerized tests, and the Harvard step test, respectively. Secondary outcomes included psychiatric symptoms, drug craving, training acceptability, and persistence.

RESULTS

Participant characteristics were matched between groups at baseline. Executive function, heart rate variability, cardiorespiratory fitness, drug craving, and most psychiatric symptoms had significant time-group interactions at posttest (p < .05, η2 = .08-.28). Compared with the attentional bias modification and control groups, the combined intervention and aerobic exercise groups improved significantly in executive function, heart rate variability, cardiorespiratory fitness, and most secondary outcomes. In addition, high-frequency heart rate variability and cardiorespiratory fitness in the aerobic exercise group were significantly higher than those in the combined intervention group.

CONCLUSIONS

Combination strategies showed comparable efficacy to aerobic exercise alone in improving executive function, psychiatric symptoms, and drug craving and significantly exceeded other conditions. For heart rate variability and cardiorespiratory fitness, aerobic exercise alone was the most effective. For acceptability and persistence, combination strategies were preferred over single-domain training and health education intervention.

Validation of StepTest4all for Assessing Cardiovascular Capacity in Young Adults

BACKGROUND

Cardiovascular capacity, expressed as maximal oxygen uptake (VO_2max), is a strong predictor of health and fitness and is considered a key measure of physiological function in the healthy adult population. The purpose of this study was to validate a specific step test (StepTest4all) as an adequate procedure to estimate cardiovascular capacity in young adults.

METHODS

The sample was composed of 56 participants, including 19 women (aged 21.05 ± 2.39 years, body mass = 57.50 ± 6.64 kg, height = 1.62 ± 0.05 m, body mass index = 22.00 ± 2.92 kg/m²) and 37 men (aged 22.05 ± 3.14 years, body mass = 72.50 ± 7.73 kg, height = 1.76 ± 0.07 m, body mass index = 23.34 ± 2.17 kg/m²). Participants were included in one of the following groups: (i) the group used to predict the VO_2max, and (ii) the group used to validate the prediction model. All participants performed the StepTest4all protocol. The step height and the intensity of the effort was determined individually. Heart rate and oxygen uptake were measured continuously during rest, effort, and recovery phases. The validation process included the following three stages: (i) mean data comparison, (ii) simple linear regression, and (iii) Bland-Altman analysis.

RESULTS

The linear regression retained, as significant predictors of the VO_2max, sex (p < 0.001) and heart rate recovery for one minute (p = 0.003). The prediction equation revealed a high relationship between measurements (R² = 63.0%, SEE = 5.58). The validation procedure revealed non-significant differences (p > 0.05) between the measured and estimated maximal oxygen uptake, high relationship (R² = 63.3%), and high agreement with Bland-Altman plots. Thus, VO_2max can be estimated with the formula: VO_2max = 22 + 0.3 · (HRR_1min) + 12 · (sex), where HRR_1min is the magnitude of the HR decrease (bpm) in one minute immediately after the step was stopped, and sex: men = 1, women = 0.

CONCLUSIONS

The StepTest4all is an adequate procedure to estimate cardiovascular capacity, expressed as VO_2max, in young adults. In addition, it is possible to determine the qualitative level of cardiovascular capacity from the heart rate recovery for one minute, more specifically, poor: <20, moderate: 20 to 34, good: 35 to 49, and excellent: ≥50. This procedure has the benefit of being simple to apply and can be used by everyone, even at home, without specialist supervision.

Effect of aerobic exercise on executive function in individuals with methamphetamine use disorder: Modulation by the autonomic nervous system

This study assessed the effects of aerobic exercise on cardiac autonomic nervous system function (based on heart rate variability [HRV]) and executive function among individuals with methamphetamine use disorder (MUD). We further examine the role of autonomic nervous system control in aerobic exercise (assessed via cardiopulmonary fitness) and executive function. A total of 330 individuals with MUD were randomly divided into exercise (n = 165) and control (n = 165) groups, who underwent eight-week aerobic exercise/health education program consisting of five 60 min sessions a week. The outcome measures included cardiopulmonary fitness, HRV time-domain and frequency-domain parameters, and executive function. Our statistical analyses comprised repeated-measures analyses of variance, correlation analyses, and mediation and moderation effect tests. The results indicated that aerobic exercise could simultaneously improve autonomic nervous system function and executive function among individuals with MUD. Moreover, the changes in cardiopulmonary fitness, high frequency HRV, and executive function were positively correlated. HRV did not significantly mediate the relationship between aerobic exercise and executive function; however, it did have a moderating effect, which was eliminated after adjusting for demographic and drug-use covariates. Among the covariates, age was the greatest confounder and was inversely proportional to cardiopulmonary function, HRV, and executive function. Cardiac autonomic nervous system function exerted a moderating, rather than a mediating, effect on the relationship between aerobic exercise and executive function. However, this potential effect was largely influenced by covariates, particularly age.

Temporal trends in step test performance for Chinese adults between 2000 and 2014

BACKGROUD/OBJECTIVE

Cardiorespiratory endurance is an excellent marker of functional endurance and health among adults. The aim of this study was to estimate temporal trends in step test performance for Chinese adults between 2000 and 2014.

METHODS

Apparently healthy adults aged 20-59 years were included. Nationally representative step test data (n = 603,977) from 2000, 2005, 2010, and 2014 were reported descriptively by the China Physical Fitness Surveillance Center. Temporal trends in means were estimated at the sex-age level for all adults and separate location/occupation groups using sample-weighted linear regression, with trends in distributional characteristics described visually and estimated as the ratio of coefficients of variation (CVs).

RESULTS

Collectively, there was a negligible improvement in mean step test performance of 0.12 standardized effect sizes (95% confidence interval (95%CI): 0.11-0.13). Negligible to small improvements were observed for all age, sex, location, and occupation groups. Variability declined substantially over time (ratio of CVs (95%CI): 0.86 (0.86-0.86)), with negligible to large improvements in those below the 10th percentile, and negligible to moderate declines in those above the 90th percentile.

CONCLUSION

There have been negligible to large improvements in step test performance for low to average performing Chinese adults since 2000, which may be meaningful to public health because low endurance is an important risk factor for all-cause mortality.

The Validity of the YMCA 3-Minute Step Test for Estimating Maximal Oxygen Uptake in Healthy Korean and Vietnamese Adults

Background

Cardiorespiratory fitness (CRF) is a fundamental component of physical fitness. While maximal oxygen uptake (VO₂max) is the gold standard for quantifying CRF, standard maximal exercise tests using direct measurements VO₂max are dependent on the availability of laboratory equipment, and thereby expensive and time consuming. Recently, an equation was formulated to indirectly estimate VO₂max using the YMCA 3-minute step test.

Methods

The study included 15 Korean (KR) and 15 Vietnamese (VN) healthy adults aged 19-35 years. All subjects completed a YMCA 3-minute step test (YMCA 3MST) and a maximal exercise treadmill test to predict VO₂max and VO₂max measures, respectively.

Results

There was a significant relationship between VO₂max predicted from the YMCA 3MST and actual VO₂max measurements from the treadmill test (r = 0.80, p < 0.0001; KR group: r = 0.81, p < 0.0001; VN group: r = 0.93, p < 0.0001). Bland-Altman analysis revealed statistical agreement between tests, although there was a systematic overestimation of 3.36 mL/kg/min for the KR group.

Conclusion

The equation for predicting VO₂max from the YMCA 3MST was validated among the study subjects. However, future research should explore the validity and reliability of the YMCA 3MST equation for estimating VO₂max in other populations.

Personality of Belgian physicians in a clinical leadership program

BACKGROUND

Physician and non-physician leadership development programs aim to improve organizational performance. Although a significant, positive relation between physicians' leadership skills and patient outcomes, staff satisfaction and staff retention has been found, physicians are not formally trained in clinical leadership skills during their physician training. A lot of current healthcare leaders were chosen to take on leadership because of their productivity, published research, solid clinical skills, or because they were great educators, Heifetz RA. Leadership Without Easy Answers; 1994 although they often do not have the skills to build a team, resulting in dysfunctional teams and having to deal with conflicts and chaos. The first steps of a Clinical Leadership Program is to gain insight in one's personality, one's personal skills and one's leadership growth potential, because this gives information on one's natural leadership style. The aim of our research is to gain insight in the personality traits of healthcare professionals who are leading teams and to check (a) whether Belgian physicians with leadership ambition, share certain preferences, (b) whether physicians differ from other healthcare staff in terms of personality, (c) whether our sample of Belgian physicians differs from a population of physicians in the United States of America.

METHODS

In-hospital physicians and non-physicians enrolled in a Clinical Leadership Program consented to participate. They explored their personal preferences across four dimensions, based on the Myers-Briggs Type Indicator (MBTI). Their most suitable MBTI profile was determined with a self-assessment and a complementary guidance of an MBTI-coach. Chi-squared tests and logistic regression were performed to check distributions across different MBTI-dimensions and to assess the relation with profession and location.

RESULTS

Among participating physicians significantly more preferences for 'Thinking' then for 'Feeling' were found. Non-physicians were found to be significantly more 'Sensing' and 'Judging' compared with physicians. No significant differences were found between physicians from our (Belgian) and the USA dataset.

CONCLUSION

Preferences of physicians proved to be different from those of non-physicians. 'ISTJ' is the most frequent personality profile both in Belgian and USA physicians.

Step oximetry test: a validation study

Introduction

Step climbing is a potentially useful modality for testing exercise capacity. However, there are significant variations between test protocols and lack of consistent validation against gold standard cycle ergometry cardiopulmonary exercise testing (CPET). The purpose of the study was to validate a novel technique of exercise testing using a dedicated device.

Methods

We built a step oximetry device from an adapted aerobics step and pulse oximeter connected to a computer. Subjects performed lung function tests, a standard incremental cycle CPET and also a CPET while stepping on and off the step oximetry device to maximal exertion. Data from the step oximetry device were processed and correlated with standard measurements of pulmonary function and cycle CPET.

Results

We recruited 89 subjects (57 years, 50 men). Oxygen uptake (VO₂) was 0.9 mL/kg/min (95% CI −3.6 to 5.4) higher in the step test compared with the gold standard cycle CPET, p<0.001. VO₂ in the two techniques was highly correlated (R=0.87, p<0.001). Work rate during stair climbing showed the best correlation with VO₂ (R=0.69, p<0.0001). Desaturation during step climbing correlated negatively with diffusion capacity for carbon monoxide (r=−0.43, p<0.005). No adverse events occurred.

Conclusions

The step oximetry test was a maximal test of exertion in the subjects studied, achieving slightly higher VO₂ than during the standard test. The test was safe to perform and well tolerated by the patients. Parameters derived from the step oximetry device correlated well with gold standard measurements. The step oximetry test could become a useful and standardisable exercise test for clinical settings where advanced testing is not available or appropriate.

The Reliability and Validity of a Modified Squat Test to Predict Cardiopulmonary Fitness in Healthy Older Men

Background

Shortcomings are noted in currently available cardiopulmonary field tests for the older adult and thus relevant research is still ongoing.

Purpose

The purpose of this study was to investigate the reliability and validity of a modified squat test and to establish a regression model for predicting aerobic fitness in the older adult.

Methods

Twenty-five healthy men aged 60 to 75 years completed this study. Each subject performed two modified squat tests with a prototype testing equipment and a maximal exercise test to determine maximal oxygen consumption. Recovery heart rates (HR) (0~30, 60~90, and 120~150 seconds) were measured following the modified squat tests. The fitness indexes included the sum of recovery HR, recovery HR index, age-adjusted recovery HR index, and immediate HR.

Results

The results revealed that the age-adjusted recovery HR index fitness had the highest intraclass correlation coefficients (ICC) of 0.9 and Pearson's correlation coefficients of 0.71, which suggested the modified squat test can reasonably assess cardiopulmonary fitness for the older adult. The regression equation for estimating aerobic power was [Formula: see text] = 16.781 + 16.732 × (age-adjusted recovery HR index) + 0.02467 × (physical activity level).

Conclusion

The modified squat test is a valid and reliable field test and thus can be an option to assess the cardiopulmonary fitness level of healthy older men in clinics or communities.

Validity of Submaximal Step Tests to Estimate Maximal Oxygen Uptake in Healthy Adults

BACKGROUND

Aerobic capacity (VO2max) is a strong predictor of health and fitness and is considered a key physiological measure in the healthy adult population. Submaximal step tests provide a safe, simple and ecologically valid means of assessing VO2max in both the general population and a rehabilitation setting. However, no studies have attempted to synthesize the existing knowledge regarding the validity of the multiple step-test protocols available to estimate VO2max in the healthy adult population.

OBJECTIVES

The objective of this study was to systematically review literature on the validity and reliability of submaximal step-test protocols to estimate VO2max in healthy adults (age 18-65 years).

DATA SOURCES AND STUDY SELECTION

A systematic literature search of the MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane Library databases was performed. The search returned 690 studies that underwent the initial screening process. To be included, the study had to (1) have participants deemed to be healthy and aged between 18 and 65 years; (2) assess VO2max by means of a submaximal step test against a graded exercise test (GXT) to volitional exhaustion; and (3) be available in English. Reference lists from included articles were screened for additional articles.

DATA ANALYSIS AND STUDY APPRAISAL METHODS

The primary outcome measures used were the validity statistics between the actual measured VO2max and predicted VO2max values, and the reported direction of the statistically significant difference between the measured VO2max and the predicted VO2max. The Quality Assessment Tool for Quantitative Studies was used to assess the risk of bias in each included study, and was adapted to the type of quantitative study design used.

RESULTS

The combined database search produced 690 studies, from which 644 were excluded during the screening process. Following full-text assessment, a further 39 studies were excluded based on the eligibility criteria detailed previously. Four additional studies were located via the reference lists of the included studies, leaving 11 studies that fulfilled the inclusion criteria and which compared eight different step-test protocols against a direct measure of VO2max incurred during a maximal GXT. Validity measures varied, with a broad range of correlation coefficients reported across the 11 studies (r = 0.469-0.95). Of the 11 studies, two reported reliability measures, demonstrating good test-retest reliability [mean -0.8 ± 3.7 mL kg(-1) min(-1) (±7.7 % of the mean measured VO2max)].

CONCLUSIONS

Considering the relationship between VO2max and various markers of health, the use of step tests as a measure of health in both the general adult population and rehabilitation settings is advocated. Step tests provide a simple, effective and ecologically valid method of submaximally assessing VO2max that can be implemented in a variety of situations within the general adult population. Future research is needed to assess the reliability of the majority of the step-test procedures reviewed. Based on the validity measures, submaximal step-test protocols are an acceptable means of estimating VO2max in the generally healthy adult population. For tracking changes in cardiorespiratory fitness, the Chester Step test appears to be an appropriate tool due to its high test-retest reliability.

Altered signaling for mitochondrial and myofibrillar biogenesis in skeletal muscles of patients with multiple sclerosis

Patients with multiple sclerosis (pwMS) experience muscle weakness and lowered muscle oxidative capacity. To explore the etiology for the development of such muscle phenotype we studied skeletal muscle adenosine monophosphate (AMP)-activated protein kinase phosphorylation (phospho-AMPKα, governing mitochondrial biogenesis) and mammalian target of rapamycin phosphorylation (phospho-mTOR, governing myofibrillar biogenesis) in pwMS. After assessment of body composition, muscle strength, exercise tolerance, and muscle fiber type, muscle phospho-AMPKα and phospho-mTOR were assessed in 14 pwMS and 10 healthy controls (part 1). Next, an endurance exercise bout was executed by 9 pwMS and 7 healthy subjects, with assessment of changes in muscle phospho-AMPKα and phospho-mTOR (part 2). Increased basal muscle phospho-AMPKα and phospho-mTOR were present in MS (P < 0.01) and independently related to MS. Correlations between muscle phospho-AMPKα or phospho-mTOR and whole-body fat mass, peak oxygen uptake, and expanded disability status scale (P < 0.05) were found. After endurance exercise muscle phospho-AMPKα and phospho-mTOR remained increased in pwMS (P < 0.01). Muscle signaling cascades for mitochondrial and myofibrillar biogenesis are altered in MS and related to the impairment and disability level. These findings indicate a link between muscle signaling cascades and the level of disability and impairment, and thus may open a new area for the development of novel therapies for peripheral muscle impairment in MS.

Validation of a single-stage fixed-rate step test for the prediction of maximal oxygen uptake in healthy adults

Healthcare professionals with limited access to ergospirometry remain in need of valid and simple submaximal exercise tests to predict maximal oxygen uptake (VO2max ). Despite previous validation studies concerning fixed-rate step tests, accurate equations for the estimation of VO2max remain to be formulated from a large sample of healthy adults between age 18-75 years (n > 100). The aim of this study was to develop a valid equation to estimate VO2max from a fixed-rate step test in a larger sample of healthy adults. A maximal ergospirometry test, with assessment of cardiopulmonary parameters and VO2max , and a 5-min fixed-rate single-stage step test were executed in 112 healthy adults (age 18-75 years). During the step test and subsequent recovery, heart rate was monitored continuously. By linear regression analysis, an equation to predict VO2max from the step test was formulated. This equation was assessed for level of agreement by displaying Bland-Altman plots and calculation of intraclass correlations with measured VO2max . Validity further was assessed by employing a Jackknife procedure. The linear regression analysis generated the following equation to predict VO2max (l min(-1) ) from the step test: 0·054(BMI)+0·612(gender)+3·359(body height in m)+0·019(fitness index)-0·012(HRmax)-0·011(age)-3·475. This equation explained 78% of the variance in measured VO2max (F = 66·15, P<0·001). The level of agreement and intraclass correlation was high (ICC = 0·94, P<0·001) between measured and predicted VO2max . From this study, a valid fixed-rate single-stage step test equation has been developed to estimate VO2max in healthy adults. This tool could be employed by healthcare professionals with limited access to ergospirometry.

Reliability and Validity of the Dutch Physical Activity Questionnaires for Children (PAQ-C) and Adolescents (PAQ-A)

BACKGROUND

This study was designed to validate the Dutch Physical Activity Questionnaires for Children (PAQ-C) and Adolescents (PAQ-A).

METHODS

After adjustment of the original Canadian PAQ-C and PAQ-A (i.e. translation/back-translation and evaluation by expert committee), content validity of both PAQs was assessed and calculated using item-level (I-CVI) and scale-level (S-CVI) content validity indexes. Inter-item and inter-rater reliability of 196 PAQ-C and 95 PAQ-A filled in by both children or adolescents and their parent, were evaluated. Inter-item reliability was calculated by Cronbach's alpha (α) and inter-rater reliability was examined by percent observed agreement and weighted kappa (κ). Concurrent validity of PAQ-A was examined in a subsample of 28 obese and 16 normal-weight children by comparing it with concurrently measured physical activity using a maximal cardiopulmonary exercise test for the assessment of peak oxygen uptake (VO2 peak).

RESULTS

For both PAQs, I-CVI ranged 0.67-1.00. S-CVI was 0.89 for PAQ-C and 0.90 for PAQ-A. A total of 192 PAQ-C and 94 PAQ-A were fully completed by both child and parent. Cronbach's α was 0.777 for PAQ-C and 0.758 for PAQ-A. Percent agreement ranged 59.9-74.0% for PAQ-C and 51.1-77.7% for PAQ-A, and weighted κ ranged 0.48-0.69 for PAQ-C and 0.51-0.68 for PAQ-A. The correlation between total PAQ-A score and VO2 peak - corrected for age, gender, height and weight - was 0.516 (p = 0.001).

CONCLUSIONS

Both PAQs have an excellent content validity, an acceptable inter-item reliability and a moderate to good strength of inter-rater agreement. In addition, total PAQ-A score showed a moderate positive correlation with VO2 peak. Both PAQs have an acceptable to good reliability and validity, however, further validity testing is recommended to provide a more complete assessment of both PAQs.

Reliability of peak O2 uptake and O2 uptake kinetics in step exercise tests in healthy subjects

To date little is known about the reliability of peak oxygen consumption (V˙O2PEAK) in incremental metronome paced step tests (IST) and the reliability of on-kinetics V˙O2 has never been studied. We aimed to study the reliability of both tests. Eleven healthy subjects performed two ISTs until exhaustion. On two different days two duplicate 4min constant metronome paced step tests (CST) were performed. V˙O2PEAK, mean response time (MRT) and phase II time constant (τ) were tested for reproducibility using the paired t-tests, in addition to the limits of agreement (LOA) and within subject coefficient of variation (COV). With a 95% LOA of 0.38 to 0.26Lmin(-1), -8.7 to 9.1s and -9.9 to 10.5s they exhibit a COV of 3%, 4.5% and 6.9% for V˙O2PEAK, MRT and τ respectively. ST are sufficiently reliable for maximal and submaximal aerobic power assessments in healthy subjects and new studies of oxygen uptake kinetics in selected patient groups are warranted.

Development and validation of an automated step ergometer

Laboratory ergometers have high costs, becoming inaccessible for most of the population, hence, it is imperative to develop affordable devices making evaluations like cardiorespiratory fitness feasible and easier. The objective of this study was to develop and validate an Automated Step Ergometer (ASE), adjusted according to the height of the subject, for predicting VO2max through a progressive test. The development process was comprised by three steps, the theoretical part, the prototype assembly and further validation. The ASE consists in an elevating platform that makes the step at a higher or lower level as required for testing. The ASE validation was obtained by comparing the values of predicted VO2max (equation) and direct gas analysis on the prototype and on a, treadmill. For the validation process 167 subjects with average age of 31.24 ± 14.38 years, of both genders and different degrees of cardiorespiratory fitness, were randomized and divided by gender and training condition, into untrained (n=106), active (n=24) and trained (n=37) subjects. Each participant performed a progressive test on which the ASE started at the same height (20 cm) for all. Then, according to the subject's height, it varied to a maximum of 45 cm. Time in each stage and rhythm was chosen in accordance with training condition from lowest to highest (60-180 s; 116-160 bpm, respectively). Data was compared with the student's t test and ANOVA; correlations were tested with Pearson's r. The value of α was set at 0.05. No differences were found between the predicted VO2max and the direct gas analysis VO2max, nor between the ASE and treadmill VO2max (p= 0.365) with high correlation between ergometers (r= 0.974). The values for repeatability, reproducibility, and reliability of male and female groups measures were, respectively, 4.08 and 5.02; 0.50 and 1.11; 4.11 and 5.15. The values of internal consistency (Cronbach's alpha) among measures were all >0.90. It was verified that the ASE prototype was appropriate for a step test, provided valid measures of VO2max and could therefore, be used as an ergometer to measure cardiorespiratory fitness.

Comparing the effectiveness of two cardiovascular prevention programmes for highly educated professionals in general practice: a randomised clinical trial

BACKGROUND

Cardiovascular disease is a major cause of mortality and morbidity and its prevalence is set to increase. While the benefits of medical and lifestyle interventions are established, the effectiveness of interventions which seek to improve the way preventive care is delivered in general practice is less so. The aim was to study and to compare the effectiveness of 2 intervention programmes for reducing cardiovascular risk factors within general practice.

METHODS

A randomised controlled trial was conducted in Belgium between 2007-2010 with 314 highly educated and mainly healthy professionals allocated to a medical (MP) or a medical + lifestyle (MLP) programme. The MP consisted of medical assessments (screening and follow-up) and the MLP added a tailored lifestyle change programme (web-based and individual coaching) to the MP. Primary outcomes were total cholesterol, blood pressure, and body mass index (BMI). The secondary outcomes were smoking status, fitness-score, and total cardiovascular risk.

RESULTS

The mean age was 41 years, 95 (32%) participants were female, 7 had a personal cardiovascular event in their medical history and 3 had diabetes. There were no significant differences found between MP and MLP in primary or secondary outcomes. In both study conditions decreases of cholesterol, systolic blood pressure, and diastolic blood pressure were found. Unfavourable increases were found for BMI (p < .05). A significant decrease of the overall cardiovascular risk was reported (p < .001).

CONCLUSIONS

Both interventions are effective in reducing cardiovascular risk. In our population the combined medical and lifestyle programme was not superior to the medical programme.

TRIAL REGISTRATION

ISRCTN23940498.

Validity of the step test for exercise prescription: no extension to a larger age range

The purpose of this study was to determine the validity of a submaximal exercise test, the Step Test Exercise Prescription (STEP), in a broad age range and in individuals in the earliest stages of Alzheimer's disease (AD). Individuals (n = 102) underwent treadmill-based maximal exercise testing and a STEP. The STEP failed to predict peak oxygen consumption (VO2peak), and was a biased estimate of VO2peak (p < .0001). Only 43% of subjects' STEP results were within 3.5 ml · kg-1 · min-1 of VO2peak. When categorized into fitness levels these 2 measures demonstrated moderate agreement (kappa = .59). The validity of the STEP was not supported in our participants, including those with AD. The STEP may not be appropriate in the clinic as a basis for exercise recommendations in these groups, although it may continue to have utility in classifying fitness in research or community health screenings.