Relevance of the measure of perceived exertion for the rehabilitation of obese patients

Higher rating of perceived exertion and lower perceived recovery following a graded exercise test during menses compared to non-bleeding days in untrained females

The underrepresentation of the female population in exercise sciences could be attributed, at least in part, to difficulty in appropriately accounting for the effects of the menstrual cycle (MC). Previous studies examining the effects of the MC on aerobic performance and subjective measures of aerobic performance show conflicting results. Purpose: The study examined how the MC affects the objective and subjective measures of aerobic performance within untrained female participants and in comparison with untrained male participants assessed at similar time intervals. Methods: Twenty-one participants (12 females and 9 males) completed a graded exercise test (GXT) on a cycle ergometer. The female participants were tested during their early follicular (EF; menses), ovulatory (O), and mid-luteal (ML) phases of the MC. The male participants were included as the control group and were randomly assigned to a menstrual cycle phase for each visit. During GXT, maximal oxygen consumption (VO2max), respiratory exchange ratio (RER), maximal heart rate (HRmax), peak blood lactate, and rating of perceived exertion (RPE) were determined. Twenty-four hours post-exercise, the perceived recovery status (PRS) was assessed. The MC phase was estimated using basal body temperature (BBT) in the female participants. Results: The male participants obtained a higher peak power and VO2max compared to the female participants (p < 0.05). All objective measures of aerobic performance did not significantly differ across the MC phases or time points that were tested. In the untrained female participants, an effect of the MC phase on RPE was found, with RPE being higher at EF (8.92 ± 0.79) compared to O (7.67 ± 1.23; p < 0.05) and ML (7.75 ± 1.06; p < 0.05). In addition, an effect of the MC phase on PRS was found, with perceived recovery being lower at EF (6.83 ± 0.94) compared to O (8.83 ± 1.12) and ML (8.67 ± 0.65; all p < 0.005) for the untrained female participants. No significant differences in RPE and PRS were found between tests in the untrained male participants. The female participants had lower perceived recovery following EF (6.83 ± 0.94) compared with the male participants (9.00 ± 1.00; p < 0.001). Conclusion: The untrained female participants perceived greater exertion during GXT and impaired recovery following GXT in EF compared to O and ML. These results may be attributed to either a drop in female sex hormone concentrations or discomfort associated with menses. The male participants did not exhibit any changes over time. Future studies using subjective parameters such as perceived exertion to track the internal load of training in the naturally menstruating female population should consider menses.

Long- and Short-Term High-Intensity Interval Training on Lipid Profile and Cardiovascular Disorders in Obese Male Adolescents

This study investigated the effects of short-term and long-term periods (8 and 16 weeks) of high-intensity interval training (HIIT) on cardiovascular components, blood lipids, and 6-min walking test performance in obese young boys (age = 16.2 ± 0.7) with >34% body fat. The participants were split into two groups: severe obesity (SOG; n = 17) and moderate obesity (MOG; n = 16). All participants performed on a cycle ergometer for 16 weeks (3 times per week) of HIIT at 100% peak power output at the ventilatory threshold and recovered at 50% of peak power. Except for BMI, both groups improved all body composition measures after 16 weeks, with a higher percentage of change (Δ) in SOG. The 6-min walking test increased in both groups (p < 0.001). Furthermore, cardiovascular variables, blood lactate concentration at rest and after 5-min post-exercise, blood lipids, and insulin concentrations improved significantly in both groups. After 16 weeks, MOG significantly improved in HR_peak, blood glucose concentration, and rating of perceived exertion (RPE), but the percentage of change (Δ) was higher in SOG for all the other variables. SOG showed a higher (Δ) waist-to-hip ratio, maximum heart rate, resting heart rate, systolic blood pressure, blood lactate at 5-min post-exercise, and triglyceride concentrations after 8 and 16 weeks of training. In conclusion, a long-term HIIT program appears to be an appropriate training approach for obese boys with extra body fat. However, considering the RPE values, short-duration training sessions should be planned.

Incorporating the Concept of Relevance in Clinical Rehabilitation Research and Its Reviews May Improve Uptake by Stakeholders

ABSTRACT

The "relevance" of research to stakeholders is an important factor in influencing the uptake of new knowledge into practice; however, this concept is neither well defined nor routinely incorporated in clinical rehabilitation research. Developing a uniform definition, measurement standards, stakeholder engagement strategies, and guiding frameworks that bolster relevance may help incorporate the concept as a key element in research planning and design. This article presents a conceptual argument for why relevance matters, proposes a working definition, and suggests strategies for operationalizing the construct in the context of clinical rehabilitation research. We place special emphasis on the importance of promoting relevance to patients, caregivers, and clinicians and provide preliminary frameworks and innovative study designs that can assist clinical rehabilitation researchers in doing so. We argue that researchers who include a direct statement regarding why and to whom a study is relevant and who incorporate considerations of relevance throughout all phases of study design produce more useful research for patients, caregivers, and clinicians, increasing its chance of uptake into practice. Consistent consideration of relevance, particularly to nonacademic audiences, during the conceptualization, study design, presentation, and dissemination of clinical rehabilitation research may promote the uptake of findings by patients, caregivers, and providers.

Affective Valence and Enjoyment in High- and Moderate-High Intensity Interval Exercise. The Tromsø Exercise Enjoyment Study

Introduction

Exercise at high intensity may cause lower affective responses toward exercise compared with moderate intensity exercise. We aimed to elucidate affective valence and enjoyment in high- and moderate-high interval exercise.

Methods

Twenty recreationally active participants (9 females, 11 males, age range: 20-51 years) underwent three different treadmill running exercise sessions per week over a 3-week period, in randomized order; (1) CE70: 45 min continuous exercise at 70% of heart rate maximum (HR_max), (2) INT80: 4 × 4 min intervals at 80% of HR_max, (3) INT90: 4 × 4 min intervals at 90% of HR_max. Pre-tests included graded submaximal steady state intensities and a test to exhaustion for determining peak oxygen uptake and HR_max. Affective valence (pleasure/displeasure) was measured before, during and after the sessions using the Feeling Scale (FS). Enjoyment was assessed before and after the sessions applying the Physical Activity Enjoyment Scale (PACES) and during the sessions using the Exercise Enjoyment Scale (EES).

Results

The participants felt lower pleasure (between-sessions effect: p = 0.02, _p η²: 0.13) during INT90 sessions (FS: 1.08, 95% CI: 0.35-1.92) compared with INT80 (FS: 2.35, 95% CI: 1.62-3.08, p = 0.052) and CE70 sessions (FS: 2.45, 95% CI: 1.72-3.18, p = 0.03), with no differences between INT80 and CE70 sessions (p = 1.00). There were higher enjoyment after INT80 sessions (PACES: 101.5, 95% CI: 95.7-107.3) versus CE70 sessions (PACES: 91.3 95% CI: 85.5-97.1, p = 0.046), and no differences between INT90 (PACES: 98.2, 95% CI: 92.4-103.4) and CE70 (p = 0.29) or INT80 (p = 1.00). For enjoyment during exercise, CE70 were perceived more enjoyable, and INT80 and INT90 less enjoyable in week 2 (EES: week x session: p = 0.01, _p η²: 0.11; CE70: 4.3, 95% CI: 3.6-4.9, INT80: 4.6, 95% CI: 3.9-5.2, INT90: 4.0, 95% CI: 3.4-4.7) and 3 (EES: CE70: 4.2, 95% CI: 3.7-4.8, INT80: 4.8, 95% CI: 4.2-5.3, INT90: 4.3, 95% CI: 3.8-4.9) than in week 1 (EES: CE70: 3.5, 95% CI: 3.0-4.0, INT80: 5.0, 95% CI: 4.5-5.5, INT90: 4.5, 95% CI: 4.0-5.0).

Conclusion

The negative affective consequences associated with high intensity interval exercise can be alleviated by keeping the intensity at or around 80% of HR_max while preserving the beneficial enjoyment responses associated with interval exercise.

Impact of Moderate Individually Tailored Physical Activity in Multiple Sclerosis Patients with Fatigue on Functional, Cognitive, Emotional State, and Postural Stability

Multiple sclerosis (MS) is a chronic disease, with fatigue syndrome as one of the main symptoms. The aim of this study was to demonstrate that moderate physical activity (MPA) may have a beneficial effect on postural stability, balance, and clinical parameters. The research group consisted of 137 randomized patients hospitalized at the Department of Neurological Rehabilitation, Medical University of Lodz. Finally, 76 patients were qualified who were divided into two groups—high fatigue (HF) and low fatigue (LF). Participants were assessed twice: before and after a 4-week MPA program using: the Expanded Disability Status Scale (EDSS), the Fatigue Severity Scale (FSS), the Mini-Mental State Examination (MMSE), the Montreal Cognitive Assessment (MoCA), the Beck Depression Inventory (BDI), and the Geriatric Depression Scale (GDS), and stabilometric platform tests were performed. Results obtained after the 4-week MPA program showed a positive effect of the MPA with differences between LF and HF groups. The MPA was more effective in MS patients with LF in cognitive functions, functional status, and postural stability but among HF patients in an emotional state, especially in MS patients below 65 years, although in total, both groups benefited from the MPA.

[Water aerobics training: selection and control of the exercise intensity using the Borg scale]

OBJECTIVE

To evaluate the opportunity of Borg scale using for applying and monitoring the aerobic training intensity in the pool as well as the relationship between the Borg scale and the heart rate (HR) in the aquatic environment.

MATERIAL AND METHODS

The study involved 11 healthy individuals (mean age 46.4±7.5 years). After a cardiopulmonary test on a treadmill and a probation lesson the training was conducted in the pool using a set of basic aerobic exercises lasting 45 minutes. During training the subjects had to maintain a load level corresponding to 12-14 points on the Borg scale. Every 10 minutes of the main training part the heart rate was calculated and the rating of perceived exertion (RPE) was determined according to the Borg scale.

RESULTS

The average heart rate in the main part of the training was 126.8±14.0 beats/min. The intensity of aerobic exercise was 82% of the maximum heart rate determined during the cardiopulmonary test and 68% of the reserve heart rate which corresponded to a high level of intensity. Between the heart rate and the Borg scale a significant correlation was found in the first period of training (r=0.67, p<0.02). At RPE 12-13 in almost ¹/₂ cases the subjects felt a subjectively lower intensity of the load than they actually performed (by heart rate) while at RPE 14 a high percentage of coincidences was observed between different measurement methods (p<0.05).

CONCLUSION

During water aerobics training the use of the Borg scale to prescribe and maintain a level of exercise allows to achieve a sufficient intensity level which is necessary to improve cardiorespiratory fitness and physical performance in order to influence risk factors for cardiovascular disease. The Borg Scale as a stand-alone method of controlling intensity when using water-based aerobic training, especially with high-intensity training should be used with caution. Further investigation is needed to determine the relation between subjective measures of exercise intensity and HR and validity of their use during water aerobics training.

Validity of differentiated ratings of perceived exertion for use during aquatic cycling

BACKGROUND

Although aquabiking has become widespread, the assessment of the intensity for aquatic cycling remains poorly defined.

METHODS

This study investigated the validity of differentiated ratings of perceived exertion (dRPE) recorded from the chest (RPE-chest) and legs (RPE-legs) during aquatic cycling and aimed to determine a simple and accurate estimate of dRPE to regulate aquabiking. Twelve active young subjects performed a pedaling task on an immersed ergocycle using randomly imposed cycling cadences ranging from 50 to 100 rpm in 3-minute steps interspersed by 3-minute active recovery periods. dRPE and cardiorespiratory responses (heart rate [HR]; percentage of heart rate peak value [%HR<inf>peak</inf>]; oxygen uptake [V̇O<inf>2</inf>]<inf>;</inf> and percentage of peak oxygen uptake [%V̇O<inf>2peak</inf>]) were measured during the last minute of each level.

RESULTS

The data described three-step relationships between dRPE and rpm. RPE-chest and RPE-legs increased linearly only for cadences between 60 and 90 rpm (r=0.81 and r=0.88, respectively; P<0.001). At these cadences, significant relationships were also observed between dRPE and all the physiological data (highest Pearson product moment for %V̇O<inf>2peak</inf>: 0.81 for RPE-chest and 0.88 for RPE-legs, P<0.0001). Last, the classic signal dominance from the legs was observed (RPE-legs>RPE-chest, P<0.0001) but was reduced compared with data obtained during dryland cycling, suggesting a modulating effect of the aquatic medium.

CONCLUSIONS

Cycling cadence was the better estimator of RPE-legs, which seemed to be the more appropriate dRPE to regulate the intensity of aquabiking in a safe range of pedaling rates.

Moderators of Perceived Effort in Adolescent Rowers During a Graded Exercise Test

Physical activity promotes mental health. A key factor is self-regulation. In the field of sports, self-regulation is related to the psychophysiological competence of rating of perceived effort (RPE). It was reported that adolescents have lower RPE competencies than adults, and it was hypothesized that this effect depends on physiological and cognitive development. The present study investigated in a sample of adolescents whether the RPE is related to basic cognitive competencies. Twelve rowers performed cognitive tests and a graded exercise test on a rowing ergometer, in which they continuously rated their perceived effort. Objective load measures and subjective perceptions were highly correlated (rho = 0.95-0.99). Furthermore, these correlations were inter-individually moderated by measures of mental speed and spontaneous flexibility. The results confirm the significance of basal cognitive competencies for conscious load perception. It is discussed whether regular sport has beneficial effects on the development of RPE competencies by enhancing cognitive regulation.

Supervised exercise following bariatric surgery in morbid obese adults: CERT-based exercise study protocol of the EFIBAR randomised controlled trial

BACKGROUND

There is increasing evidence of weight regain in patients after bariatric surgery (BS), generally occurring from 12 to 24 months postoperatively. Postoperative exercise has been suggested to ad long-term weight maintenance and to improve physical function in BS patients. However, there are a limited number of intervention studies investigating the possible benefits of exercise in this population. The aim of the current report is to provide a comprehensive CERT (Consensus on Exercise Reporting Template)-based description of the rationale and details of the exercise programme implemented in the EFIBAR Study (Ejercicio FÍsico tras cirugía BARiátrica), a randomised controlled trial investigating the effects of a 16-week supervised concurrent (aerobic and strength) exercise intervention program on weight loss (primary outcome), body composition, cardiometabolic risk, physical fitness, physical activity and quality of life (secondary outcomes) in patients with severe/morbid obesity following bariatric surgery.

METHODS

A total of 80 BS patients [60-80% expected women, aged 18 to 60 years, body mass index (BMI) ≥ 40 kg/m2 or ≥ 35 kg/m2 with comorbid conditions)] will be enrolled in the EFIBAR Randomized Control Trial (RCT). Participants allocated in the exercise group (n = 40) will undertake a 16-week supervised concurrent (strength and aerobic) exercise programme (three sessions/week, 60 min/session), starting 7 to 14 days after surgery. The rationale of the exercise programme will be described following the CERT criteria detailing the 16 key items. The study has been reviewed and approved by the Ethics Committee of the Torrecárdenas University Hospital (Almería, Spain) (ref. N° 76/2016).

DISCUSSION

The present study details the exercise programme of the EFIBAR RCT, which may serve: 1) exercise professionals who would like to implement an evidence-based exercise programme for BS patients, and 2) as an example of the application of the CERT criteria.

TRIAL REGISTRATION

The trial was prospectively registered at Clinicaltrials.gov NCT03497546 on April 13, 2018.

Competencies for rating perceived exertion in amateur soccer players with and without intellectual disabilities

BACKGROUND

Perception of exertion is essential for self-regulation in sports. The ability to rate perceived exertion (RPE) is regarded as psychophysiological competence, although cognitive components of RPE are largely unknown. The present study tested the hypothesis that cognitive processing speed, perseveration and figural fluency correlate with RPE.

METHODS

The present study tested relationships between the performance in neuropsychological tests and the competence for RPE assessed during soccer training in 30 adults with and 22 adults without intellectual disabilities.

RESULTS

Mean correlation coefficients for RPE and heart rate differed significantly between participants with intellectual disabilities (r = .41) and participants without intellectual disabilities (r = .71). The variance of RPE could be partially explained by neuropsychological performance measures reflecting cognitive processing speed and perseveration and by age.

CONCLUSIONS

The results point to an impaired perception of exertion in people with intellectual disabilities, which can be partially explained by individual neuropsychological competencies.

High Intensity Long Interval Sets Provides Similar Enjoyment as Continuous Moderate Intensity Exercise. The Tromsø Exercise Enjoyment Study

OBJECTIVE

High intensity interval exercise sessions with interval sets over 3 min may provide superior cardiorespiratory fitness benefits. To our knowledge, the exercise enjoyment of interval sets over 3 min is not yet elucidated. The aim of this study was to examine exercise enjoyment following one session with four intervals of 4 min high intensity exercise (HIIE) versus one session of 45 min moderate intensity continuous exercise (CE) in iso-caloric conditions using a randomized crossover design.

METHODS

Seven young healthy participants were recruited to undergo two different exercise sessions in a randomized order: (1) 4 × 4 min intervals at >90% of maximum heart rate (HR max ) with 3 min of rest between interval sets, and (2) 45 min CE at 70% of HR max . Peak oxygen uptake and HR max were evaluated prior to the experiment. The participants reported their perceived exercise enjoyment using the 18-item physical activity enjoyment scale (PACES) questionnaire and their rating of perceived exertion (RPE) using Borg's 6-20 scale.

RESULTS

There was no difference in the PACES score between the high intensity interval exercise session [median: 95.5 (inter-quartile range: 21.8)] and the moderate intensity CE session [91.0 (13.5), p = 0.36, r = -0.22]. The participants reported a higher RPE in the high intensity interval exercise session [16.5 (2.0)] compared with the CE session [9.0 (2.0), p = 0.01, r = -0.88].

CONCLUSION

Similar exercise enjoyment was reported following four high intensity intervals of 4 min compared with a moderate intensity CE session in this randomized crossover study with iso-caloric conditions. If enjoyment is a mediating factor for engaging in exercise, one should expect a similar probability of exercise adherence following high intensity 4 min intervals and continuous moderate intensity exercise when prescribing aerobic exercise as preventive medicine.

Effectiveness of a Functional Rehabilitation Program After Bariatric Surgery: a Pilot Study

BACKGROUND

Beyond obesity-related comorbidities, overweight patients have a high risk of developing osteoarticular pathologies. Moreover, weight loss following bariatric surgery induces a decrease in fat mass but also in muscle mass, thus affecting the physical capacities of these patients. Functional rehabilitation is a solution to correct these imbalances. The aim of this study was to evaluate the effectiveness of a functional rehabilitation program after bariatric surgery.

METHODS

Twenty-three patients with severe obesity (BMI = 37.9 ± 5.7 kg/m²; 41.1 ± 12.9 years) participated in a functional rehabilitation protocol, 2 months after sleeve gastrectomy. Rehabilitation program consisted of 20 sessions of 1h30 (two sessions per week), based on endurance training, muscle strengthening, and proprioception work. An initial and final assessment included bioelectrical impedance measurements, questionnaires, and physical function tests.

RESULTS

All impedance parameters were significantly improved in 20 sessions: % excess weight loss (%EWL) from 27.6 ± 9.1 to 51.1 ± 13.4% and % fat-free mass from 52.7 ± 5.6 to 57.6 ± 6.7%. Waist and hip circumferences were significantly reduced in 20 sessions: from 107.4 ± 13.7 to 94.5 ± 12.6 cm and from 120.5 ± 12.4 to 108.7 ± 11.7 cm, respectively (p < 0.001). Physical function tests were significantly improved between the 1st and the 20th sessions (p < 0.001). The cycloergometer stress test progressed from 77.7 ± 24.1 to 93.6 ± 27.2 W, and the sit-to-stand test from 20 ± 5.2 to 24.8 ± 7.6 flexions in 30 s. The Quality Of Life, Obesity and Dietetics (QOLOD) scale increased by 12.6%.

CONCLUSIONS

The functional rehabilitation protocol of 20 sessions significantly improved patients' body composition, functional tests, and quality of life. The standardization of tests and sessions allowed to objectively assess progress.

Greater effects of high- compared with moderate-intensity interval training on cardio-metabolic variables, blood leptin concentration and ratings of perceived exertion in obese adolescent females

This study examined the effects of high- vs. moderate-intensity interval training on cardiovascular fitness, leptin levels and ratings of perceived exertion (RPE) in obese female adolescents. Forty-seven participants were randomly assigned to one of three groups receiving either a 1:1 ratio of 15 s of effort comprising moderate-intensity interval training (MIIT at 80% maximal aerobic speed: MAS) or high-intensity interval training (HIIT at 100% MAS), with matched 15 s recovery at 50% MAS, thrice weekly, or a no-training control group. The HIIT and MIIT groups showed improved (p < 0.05) body mass (BM), BMI Z-score, and percentage of body fat (%BF). Only the HIIT group showed decreased waist circumference (WC) (p = 0.017). The effect of exercise on maximal oxygen uptake (VO2max) was significant (p = 0.019, ES = 0.48 and p = 0.010, ES = 0.57, HIIT and MIIT, respectively). The decrease of rate-pressure product (RPP) (p < 0.05, ES = 0.53 and ES = 0.46, HIIT and MIIT, respectively) followed the positive changes in resting heart rate and blood pressures. Blood glucose, insulin level and the homeostasis model assessment index for insulin decreased (p < 0.05) in both training groups. Significant decreases occurred in blood leptin (p = 0.021, ES = 0.67 and p = 0.011, ES = 0.73) and in RPE (p = 0.001, ES = 0.76 and p = 0.017, ES = 0.57) in HIIT and MIIT, respectively. In the post-intervention period, blood leptin was strongly associated with %BF (p < 0.001) and VO2max (p < 0.01) in the HIIT and MIIT groups, respectively, while RPE was strongly associated with BM (p < 0.01) in the HIIT group. The results suggest that high-intensity interval training may produce more positive effects on health determinants in comparison with the same training mode at a moderate intensity.

A hard/heavy intensity is too much: The physiological, affective, and motivational effects (immediately and 6 months post-training) of unsupervised perceptually regulated training

Background/Objective

There are several practical and theoretical advantages to perceptually regulated training, including its simplicity of use and potential to influence exercise motivation. The study objective was to examine if perceptually regulated training at ratings of perceived exertion (RPE) of 13 and 15 resulted in significant increases in aerobic fitness, reductions in metabolic risk factors, and changes in motivational constructs following an 8-week training program and at follow up 6 months after.

Methods

Following stratified randomization based on estimated aerobic capacity and sex, sedentary volunteers (n = 63; men = 21) were allocated to one of three groups: RPE 13, RPE 15, and control. The participants completed baseline, post-training, and 6-months post-training assessments for aerobic fitness, metabolic risk factors, and motivational constructs. The participants' acute exercise training responses (affect, competence, enjoyment, and work rate) were also recorded.

Results

The data support the fitness and motivational construct hypotheses but not the metabolic risk factor hypothesis. Aerobic fitness increased from the baseline to post-training in both RPE groups, with the increase maintained 6 months post-training only in the RPE 13 group. Exercise autonomy increased over the training program, with exercise competence and affect more positive in the RPE 13 group than in the RPE 15. However, the training programs did not reduce the metabolic risk factors, and attrition levels were high. Unsupervised training at RPE 13 and RPE 15 did improve fitness, but as hypothesized, this was not maintained in the RPE 15 group 6 months post-training.

Conclusion

The motivational processes associated with RPE 13 regulated exercise (greater competence and autonomy and more positive affect) potentially explain the maintained fitness in this group.

Obesity-related chronic lymphoedema-like swelling and physical function

BACKGROUND

People with severe obesity (body mass index [BMI] > 40 kg/m(2)) have an 85% higher mortality than people with a healthy BMI. Poor physical function may contribute to this excess mortality. Lymphoedema-like swelling can affect the legs of severely obese people with normal lymphoscintigraphy.

AIM

We sought to determine the relationship between the presence of lymphoedema-like swelling and physical function in the severely obese.

DESIGN AND METHODS

In people with severe obesity, we ascertained whether lower leg lymphoedema-like swelling was present and determined the circumference of the lower leg, time taken to ascend and descend a 17-cm step 50 times and time taken to walk 500 m.

RESULTS

The 330 participants, 33% of whom were male, were aged 43.4 ± 12.7 years (mean ± standard deviation) and had a BMI of 51.7 ± 8.4 kg/m(2). Lymphoedema-like swelling was present in approximately one-third (n = 108) in whom a prior history of cellulitis and venous thromboembolism was more common (relative risks 6.16 and 3.86, respectively) than in those without lymphoedema-like swelling. Participants with lymphoedema-like swelling, compared with non-affected counterparts, had a higher lower leg circumference (35.0 ± 7.1 vs. 32.4 ± 4.8 cm), a slower step speed (0.40 ± 0.12 vs. 0.43 ± 0.10 steps/s) and a slower walking speed (0.97 ± 0.37 vs. 1.08 ± 0.30 m/s, P < 0.05 for all comparisons).

CONCLUSIONS

In this cross-sectional study, 33% of our severely obese participants had lymphoedema-like swelling. Participants with lymphoedema-like swelling had worse physical function than those without. This association was independent of BMI. The presence of obesity-related chronic lymphoedema-like swelling should lead to interventions that improve physical function.

Prediction of maximal or peak oxygen uptake from ratings of perceived exertion

Maximal or peak oxygen uptake (V˙O2 max and V˙O2 peak , respectively) are commonly measured during graded exercise tests (GXTs) to assess cardiorespiratory fitness (CRF), to prescribe exercise intensity and/or to evaluate the effects of training. However, direct measurement of CRF requires a GXT to volitional exhaustion, which may not always be well accepted by athletes or which should be avoided in some clinical populations. Consequently, numerous studies have proposed various sub-maximal exercise tests to predict V˙O2 max or V˙O2 peak . Because of the strong link between ratings of perceived exertion (RPE) and oxygen uptake (V˙O2), it has been proposed that the individual relationship between RPE and V˙O2 (RPE:V˙O2) can be used to predict V˙O2 max (or V˙O2 peak) from data measured during submaximal exercise tests. To predict V˙O2 max or V˙O2 peak from these linear regressions, two procedures may be identified: an estimation procedure or a production procedure. The estimation procedure is a passive process in which the individual is typically asked to rate how hard an exercise bout feels according to the RPE scale during each stage of a submaximal GXT. The production procedure is an active process in which the individual is asked to self-regulate and maintain an exercise intensity corresponding to a prescribed RPE. This procedure is referred to as a perceptually regulated exercise test (PRET). Recently, prediction of V˙O2max or V˙O2 peak from RPE:V˙O2 measured during both GXT and PRET has received growing interest. A number of studies have tested the validity, reliability and sensitivity of predicted V˙O2 max or V˙O2 peak from RPE:V˙O2 extrapolated to the theoretical V˙O2 max at RPE20 (or RPE19). This review summarizes studies that have used this predictive method during submaximal estimation or production procedures in various populations (i.e., sedentary individuals, athletes and pathological populations). The accuracy of the methods is discussed according to the RPE:V˙O2 range used to plot the linear regression (e.g., RPE9–13 versus RPE9–15 versus RPE9–17 during PRET), as well as the perceptual endpoint used for the extrapolation (i.e., RPE19 and RPE20). The V˙O2 max or V˙O2 peak predictions from RPE:V˙O2 are also compared with heart rate-related predictive methods. This review suggests that V˙O2 max (or V˙O2 peak ) may be predicted from RPE:V˙O2 extrapolated to the theoretical V˙O2 max (or V˙O2 peak) at RPE20 (or RPE19). However, it is generally preferable to (1) extrapolate RPE:V ˙ O 2 to RPE19 (rather than RPE20); (2) use wider RPE ranges (e.g. RPE ≤ 17 or RPE9–17) in order to increase the accuracy of the predictions; and (3) use RPE ≤ 15 or RPE9–15 in order to reduce the risk of cardiovascular complications in clinical populations.

Association between vitamin D status and physical function in the severely obese

CONTEXT

Mortality is 85% higher in severely obese subjects (body mass index [BMI] > 40 kg/m(2)) than in subjects with a healthy BMI; poor physical function may be contributory. Hypovitaminosis D is common in obese subjects and is associated with physical dysfunction in the elderly.

OBJECTIVE

We determined the relationship between vitamin D status and physical function in severely obese subjects.

DESIGN, SETTING, AND PATIENTS

We conducted a clinic-based, cross-sectional study of severely obese subjects. Participants were stratified into three groups according to the Institute of Medicine (IOM) vitamin D status categorization.

MAIN OUTCOME MEASURES

We compared levels of self-reported activity and times taken to walk 500 m and to ascend and descend a 17-cm step 50 times.

RESULTS

We recruited 252 subjects (age, 43.7 ± 11.2 y; BMI, 50.7 ± 9.7 kg/m(2)); 25-hydroxyvitamin D (25OHD) concentrations were less than 30 nmol/L in 109 participants. Participants with a 25OHD > 50 nmol/L, compared to those with a 25OHD < 30 nmol/L, had the highest activity levels (3.1 ± 3.4 h/wk versus 1.5 ± 2.5 h/wk; P = .015) and the shortest 500-m walk times (6.2 ± 1.1 min versus 7.4 ± 1.5 min; P = .003). Serum 25OHD concentrations had a weakly positive association with activity level (r = 0.19; P = .008) and a moderately negative association with 500-m walk time (r = -0.343; P < .001).

CONCLUSIONS

Vitamin D status had a significant relationship with physical activity and physical function in this cohort of severely obese subjects. Low activity levels are likely to perpetuate the problem of hypovitaminosis D due to less time spent outdoors. Studies exploring the effects of vitamin D supplementation in this population are warranted.

Positive effect of the use of accelerometry on lifestyle awareness of overweight hypertensive patients

PURPOSE

Sedentary habits are strongly associated with increase of cardiovascular risk factors. The present study aimed to verify the role of accelerometry in identifying sedentary behavior, and the possible short term positive effect of this intervention on some anthropometric variables in a group of patients with cardiovascular risks factors.

METHODS

To quantify daily Spontaneous Motor Activity (SMA) levels and identify sedentary behavior, an accelerometer was employed, in addition to a simple questionnaire, in a group of overweight, hypertensive subjects. A personalized unsupervised 3 month long physical exercise program was planned. After this time, acceleroometry was again undertaken to analyze the impact of the intervention on some life style parameters, including the number of the steps taken daily, and Physical Activity Level (PAL). In addition, body water balance, weight, and Body Mass Index (BMI) were also evaluated.

RESULTS

Assessment of physical activity by accelerometry identifies sedentary behaviors in a larger number of individuals. After three months of regular unsupervised aerobic exercise, PAL improved from 1.56 ±0.1 to 1.68±0.2 with P<0.005, weight (kg) reduced from 85.13 ± 20 to 83.10 ± 19 (P<0.05), BMI from 29.58 to 28.7 (P<0.05).

CONCLUSION

Accelerometry allows to objectify PAL, and can be used to monitor improvement of variables strongly related to cardiovascular risk.