Piet Rispens

THE RELATIONSHIP BETWEEN COMFORTABLE AND MOST METABOLICALLY EFFICIENT WALKING SPEED IN PERSONS WITH UNILATERAL ABOVE-KNEE AMPUTATION

Walking is most efficient when the least energy is spent over a certain distance. In six normal male subjects and 11 males with above-knee amputation the comfortable self-selected walking speeds and the most metabolically efficient walking speeds were determined. For that purpose energy expenditure was measured per second and per meter at six incremental walking speeds. Heart and step rate were registrated also at each walking speed. The results showed that in subjects who have not undergone amputation the comfortable walking speed is the same as the most efficient walking speed. However, in the above-knee amputee group, the comfortable walking speed is lower than the most efficient walking speed. When both groups walked at their own efficient walking speed they had the same energy expenditure per second.

Differential effects of high-frequency versus low-frequency exercise training in rehabilitation of patients with coronary artery disease

OBJECTIVES We sought to study the influence of frequency of exercise training during cardiac rehabilitation on functional capacity (i.e., peak oxygen consumption [VO2] and ventilatory anaerobic threshold [VAT]) and quality of life (QoL). BACKGROUND Although the value of cardiac rehabilitation is now well established, the influence of the different program characteristics on outcome has received little attention, and the effect of frequency of exercise training is unclear. Functional capacity is regularly evaluated by peak VO2 but parameters of submaximal exercise capacity such as VAT should also be considered because submaximal exercise capacity is especially important in daily living. METHODS Patients with coronary artery disease (n = 130, 114 men; mean age 52 +/- 9 years) were randomized to either a high- or low-frequency program of six weeks (10 or 2 exercise sessions per week of 2 h, respectively). Functional capacity and QoL were assessed before and after cardiac rehabilitation. Global costs were also compared. RESULTS Compared with baseline, mean exercise capacity increased in both programs: for high- and low-frequency, respectively: peak VO2 = 15% and 12%, Wmax = 18% and 12%, VAT = 35% and 12% (all p < 0.001). However, when the programs were compared, only VAT increased significantly more during the high-frequency program (p = 0.002). During the high-frequency program, QoL increased slightly more, and more individuals improved in subjective physical functioning (p = 0.014). We observed superiority of the high-frequency program, especially in younger patients. Mean costs were estimated at 4,455 and 2,273 Euro, respectively, for the high- and low-frequency programs. CONCLUSIONS High-frequency exercise training is more effective in terms of VAT and QoL, but peak VO2 improves equally in both programs. Younger patients seem to benefit more from the high-frequency training.

Change in self-efficacy during cardiac rehabilitation and the role of perceived overprotectiveness

Self-efficacy (SE) is an important outcome following cardiac rehabilitation (CR) when claiming benefits to patients and improving existing programs. This study evaluated change in SE during 6 weeks of multidisciplinary CR with either a high or low-frequency exercise training program. The role of overprotectiveness of the spouse, as it potentially counteracts improvement in SE, was examined. Coronary patients (n = 114) were randomized into both types of program. Overprotectiveness (patient perception) was assessed prior to rehabilitation. Self-efficacy in the domains controlling symptoms (SE-CS) and maintaining function (SE-MF), were assessed prior to and immediately after rehabilitation. Three findings pertain to program improvement: (1) As predicted, the low-frequency program enhanced SE-CS more than the high-frequency program, suggesting that experiencing success in daily activities and active engagement of the patient seem more decisive factors in improving SE than the frequency of exercise. (2) Changes in SE in both programs fell short of clinical meaning, suggesting the need to use self-efficacy theory more vigorously. (3) Overprotectiveness significantly predicted adverse change in SE in the high-frequency program, suggesting the need to include counseling for cardiac couples in CR when applicable.

Ten-metre walk, with or without a turn?:

Objective: To compare results obtained using different procedures to measure 10-metre walking time. Design: Walking was timed over a straight 10 m, and over 5 m with return. Further, the time taken to turn was measured directly. Setting: Rehabilitation department of a university hospital. Subjects: Patients who had walking disability after stroke. Results: In the group of 43 patients, the time taken to walk 5 m and return was 3.3 (SD 5.0) s longer than the time to walk 10 m straight, but there was a large variation with some patients walking faster. The measured time to turn in a second group of 27 patients was 3.2 (SD 1.6) s. The times taken to walk 10 m straight and 5 m and return, and the time taken to turn were all highly correlated (r = 0.69 or more). Conclusions: Timing walking over 5 m with a return is an acceptable alternative to the 10 m straight walk, but the actual time taken varies. On average, the walk with a turn is 3.2 s longer but in individual patients the difference may be much more or less. Sometimes the walk with a turn is even faster than that without.

Individual assessment of intensity-level for exercise training in patients with coronary artery disease is necessary

BACKGROUND Target intensity-level of exercise training in patients with coronary artery disease is adjusted usually by a target heart rate (THR). This THR is aimed to be at or nearby the anaerobic threshold (AT) and is calculated commonly from parameters of regular exercise training, instead of an actual measurement of AT and its related heart rate. Therefore, this study evaluated whether a calculation is reliable. METHODS In 91 male patients (age 52+/-9 years) exercise capacity was measured after a recent (>4 weeks) coronary event. AT was compared with peak exercise capacity and heart rate at AT was compared with THR, using the Karvonen method. RESULTS Mean AT (18.2 ml/min/kg, range 9.2-32.2) and mean peak V(O2) (24.5, range 10.9-43.9) were slightly decreased (respectively 0.83 and 0.79 of predicted). When related to peak exercise capacity, AT showed a large inter-individual variation. For example, heart rate at AT ranged from 0.55 to 0.96 of peak heart rate. As a result heart rate at AT varied considerably with THR. The mean THR, although significantly higher, correlated well with mean heart rate at AT (respectively, 109 and 105/min, P<0.01; r=0.86, P<0.001). However, in an important number of patients heart rate at AT was more than 10% below or above THR (respectively, 30 and 7%). CONCLUSION In individual exercise prescription for cardiac rehabilitation the training level should be determined directly, and not indirectly by calculation from heart rate parameters of exercise testing.

A Dutch Version of the Social Support for Exercise Behaviors Scale

We studied the reliability of a Dutch version of the Social Support for Exercise Behaviors Scale, originally developed by Sallis, Grossman, Pinski, Patterson, and Nader, using a sample of 461 older adults between 55 and 65 years of age. Cronbach alpha for the three subscales was calculated, respectively, as .69, .71, and .26, which are lower than the alphas reported in the original study. This may be due to the cultural differences between The Netherlands and the United States and differences between the samples of the two studies.

The Groningen Enjoyment Questionnaire: A measure of enjoyment in leisure-time physical activity

The purpose of this study was to develop a short and easily used questionnaire to measure enjoyment in leisure-time physical activity. The first part of the study involved the questionnaires composition. A set of 30 positively formulated potential items was generated and subsequently completed by 59 subjects. We used these results to trim the questionnaire to 10 items. In the second part of the study, the questionnaire was administered to 82 subjects and research was done into reliability and validity. The results indicate that the Groningen Enjoyment Questionnaire can be considered reliable and valid.