Ugur Dal

Determination of preferred walking speed on treadmill may lead to high oxygen cost on treadmill walking.

The energy consumption of walking relates to the intensity of physical effort and can be affected by the alterations in walking speed. Therefore, walking speed can be accepted as a crucial, determinant of energy consumption measurement for a walking test. We aimed to investigate the differences in preferred walking speed (PWS) determined both on overground and on a treadmill and, to measure walking energy expenditure and spatio-temporal parameters of gait on a treadmill at both, speeds. Participants (n=26) walked on a treadmill at two pre-determined speeds for 7 min while, indirect calorimetry measurements were being performed. Spatio-temporal parameters were collected, by video-taping during each walking session on a treadmill. The average overground preferred walking speed (O-PWS) was 85.96+/-12.82 m/min and the average treadmill preferred walking speed (T-PWS), was 71.15+/-13.85 m/min. Although T-PWS was lower, oxygen cost was statistically higher when, treadmill walking at T-PWS (0.158+/-0.02 ml/kg/m) than when the treadmill walking at O-PWS, (0.1480+/-0.02 ml/kg/m). Cadence (127+/-9.13 steps/min), stride (134.02+/-14.09 cm) and step length (67.02+/-6.90 cm) on the treadmill walking at O-PWS were significantly higher than cadence (119+/-10 steps/min), stride (117.96+/-14.38 cm) and step length (59.13+/-7.02 cm) on the treadmill walking at TPWS. In conclusion, walking on treadmill using O-PWS is more efficient than walking on treadmill using TPWS, in walking tests. Since using T-PWS for treadmill walking tests overestimates the oxygen cost of walking, O-PWS should be used for oxygen consumption measurement during treadmill walking tests.

The effect of hinged ankle-foot orthosis on gait and energy expenditure in spastic hemiplegic cerebral palsy.

Purpose. To assess the effectiveness of a hinged ankle-foot orthoses on gait impairments and energy expenditure in children with hemiplegic cerebral palsy (CP) whom orthoses were indicated to control equines. Method. Eleven children (seven males, four females) who had a diagnosis of hemiplegic cerebral palsy were included in the study. Each child underwent gait analysis and energy consumption studies with and without ankle-foot orthosis (AFO). The AFOs were all custom-made for the individual child and had plantarflexion stop at 0° with no dorsoflexion stop. The Vicon 512 Motion analysis system was used for gait analysis. Walking energy expenditure measurements were done with breath by breath method using an open-circuit indirect calorimeter (Vmax 29c, Sensormedics, USA). All tests were carried out on the same day with enough resting period. Results. AFO application, as compared with the barefoot condition improved walking speed, stride length and single support time. Double support time was decreased significantly with AFOs and no change in cadance. Ankle dorsiflexion at initial contact, midstance and midswing showed significiant increase. Knee flexion at initial contact was decreased and no significant change in maximum knee extension at stance and maximum knee flexion at swing was obtained. The oxygen consumption was significantly reduced during AFO walking. Conclusion. The hinged AFO is useful in controlling dynamic equinus deformity and reducing the energy expenditure of gait in children with hemiplegic spastic cerebral palsy.

Basal Metabolic Rate and Autonomic Nervous System Dysfunction in Men With Spinal Cord Injury

Objectives: The purpose of this study was to determine the relationship between autonomic nervous system dysfunction and basal metabolic rate (BMR), and the effect of spasticity on basal metabolic rate.

Fibromyalgia Syndrome Patients Optimize the Oxygen Cost of Walking by Preferring a Lower Walking Speed

Objectives The aim of the study is to investigate the effect of fibromyalgia syndrome [FMS] on the preferred walking speed [PWS], energy expenditure at rest, and oxygen cost of walking. Methods Fifteen women with FMS and 15 healthy matched female subjects participated in our study. All patients were newly diagnosed and had no medication for FMS. The energy expenditure of FMS individuals was measured by using indirect calorimetry during resting and walking at PWS. Results The resting energy expenditure in healthy subjects [Group 1] was 1115.08 ± 154.33 kcal/day and that in FMS patients [Group 2] was 1253.48 ± 212.94 kcal/day; there was no statistical difference between the groups [P > 0.05]. The mean PWSs in Groups 1 and 2 were 81.22 ± 9.10 and 71.42 ± 6.61 m/min, respectively. The difference between the PWSs in Groups 1 and 2 was statistically significant [P < 0.05]. The mean oxygen consumption in the first walking trail was 12.95 ± 2.62 and 11.83 ± 1.68 mL/kg/min in Groups 1 and 2, respectively [P > 0.05]. The mean oxygen cost of the first walking trial in Groups 1 and 2 was 0.16 ± 0.02 and 0.17 ± 0.02 mL/kg/m, respectively; the difference was not significant [P > 0.05]. Conclusion The PWS of patients with FMS was lower than that of healthy controls. The oxygen cost and consumption were similar in both groups in our study. This study demonstrates that FMS individuals optimize the oxygen cost of walking by preferring a lower walking speed.

Resting Energy Expenditure in Normal-Weight and Overweight/Obese Subjects Was Similar Despite Elevated Sympathovagal Balance

Objective: Alterations in the autonomic nervous system (ANS) may cause impairment in the metabolic processes that can lead to weight gain. The purpose of this study was to determine the difference between the resting energy expenditure (REE) and the resting ANS activity in overweight/obese and normal-weight healthy subjects. Method: Group 1 consisted of 18 subjects with BMI > 25 kg/m2, and 20 subjects with BMI ranging from 20 to 25 kg/m2 formed group 2. Measurements of low-frequency (LF) and high-frequency (HF) power components expressed in normalized units (LFnu, HFnu) and LF/HF ratio were assessed for analysis of heart rate variability, and simultaneously REE measurement was performed. Results: The mean LFnu (27.2% increased) and the LF/HF were higher and the mean HFnu was lower (29.9% decreased) in group 1 than in group 2 (p < 0.01). Although a statistical difference was observed in REE between groups, REE per kilogram corrected for fat-free mass (REEFFMcorr) was 21.47 ± 2.92 kcal/day/kg in group 1, and 21.56 ± 1.90 kcal/day/kg in group 2, and this difference was not statistically significant (p > 0.05). Conclusion: We concluded that REEFFMcorr in overweight/obese and normal-weight subjects were similar despite elevated sympathovagal balance in overweight/obese individuals, and REEFFMcorr should be used to avoid misestimating the REE in obese and normal-weight subjects.

Alterations in energy consumption and plantar pressure distribution during walking in young adults with patellofemoral pain syndrome

Objective The aim of this study was to determine the alterations of walking energy expenditure and plantar pressure distribution in young adults with patellofemoral pain syndrome (PFPS). Methods Thirty five individuals (mean age: 21.31 ± 1.76) with PFPS constituted the patient group and forty healthy participants (mean age: 21.40 ± 2.11) the control group. Preferred walking speeds (PWS) were determined on the over ground. Individuals walked on a treadmill for 7 min at their PWS and 30% above PWS and oxygen consumption was recorded via a metabolic analyzer. Net oxygen consumption was calculated for each walking trial. Borg scale was applied to assess perceived exertion during walking trial. Plantar pressure distributions were measured by a pedobarography device. Plantar area was subdivided into six zones to evaluate the dynamic plantar pressure data. Results The mean PWS of PFPS and control groups were 4.69 ± 0.51 and 4.52 ± 0.60 km/h, respectively (p > .09). No significant difference was observed in energy expenditure during walking at PWS between 2 groups while oxygen consumption during 30% above PWS was higher in patient group (18.72 ± 3.75 and 16.64 ± 3.27) (p = .007). Net oxygen consumption was also found to be higher in PFPS group (15.12 ± 3.62 and 13.04 ± 3.24) (p = .005). The mean Borg scores were significantly higher in PFPS group at each walking trials (p < .001). No statistically significant difference was found between weight distribution (%) of symptomatic and nonsymptomatic extremity (50.45 ± 3.92% and 49.56 ± 3.93%, respectively) (p = .509). Dynamic pedobarography parameters were not different between 2 groups, and also between symptomatic and nonsymptomatic extremities (p > .05). Conclusion Although, rate of perceived exertion and energy expenditure during walking at 30% above PWS are affected negatively in young adults with PFPS, we may speculate that energy consumption and plantar pressure distribution can be compensated by a physiologic adaptation mechanism during walking at PWS. Level of evidence Level III, Therapeutic Study.

Effect of Osteoporosis on Energy Expenditure of Resting and Daily Activities in Postmenopausal Women

Summary Objective: The purpose of our study was to determine the effect of osteoporosis on energy expenditure and daily activities of postmenopausal women. Materials and Methods: Eighteen recently diagnosed postmenopausal osteoporotic women without any fractures participated in this study. They were matched for age and body mass index with 19 postmenopausal nonosteoporotic women. Energy expenditure of postmenopausal women was measured using an indirect calorimetry during resting, sitting, standing and walking at speeds of 50 m/min and 70 m/min. Quality of life of subjects was evaluated with the short form-36 (SF-36) questionnaire. Results: There were no significant differences between groups for VO2 (ml/min) during resting, sitting, standing, and walking at speeds of 50 m/min and 70 m/min. Bone mineral density (BMD) of the proximal femur was correlated with resting energy expenditure (REE) (r=0.49, p= 0.03) in postmenopausal osteoporotic women. The SF-36 bodily pain subscale score was significantly higher in postmenopausal osteoporotic women (74.33±20.86) than in nonosteoporotic women (58.10±17.09). The power of the study for detecting the differences was calculated as 71%. Conclusion: The results seem to indicate that there is a relationship between BMD and REE in postmenopausal osteoporotic women. Although pain scores were higher in osteoporotic women, it was detected that they did not affect the energy expenditure of resting and at different physical activity levels. While determining the caloric intake of osteoporotic women and energy expenditure estimation in various daily physical activities, it can be taken into account that energy expenditure of osteoporotic women is similar to nonosteoporotic women. Turk J Phys

A new upper extremity sparing non-weight bearing orthosis

OBJECTIVES Axillary and forearm crutches are commonly utilized in the treatment of foot and ankle injuries. In order to decrease the energy expenditure during mobilization, to prevent upper extremity complications, and to let the upper extremity free for other usages, we designed a new orthosis. The study is conducted to compare walking energy parameters of this newly designed orthosis with the axillary and forearm crutches. MATERIALS AND METHODS 10 healthy young male volunteers walked on treadmill with three different orthoses in randomized order. Oxygen expenditure, oxygen cost, rate of perceived exertion (Borg scale), and observer stability assessment were analyzed. RESULTS Concerning oxygen consumption, perceived exertion, and observer stability assessment, the new device was found superior to the other devices (P<0.05). The new orthosis was superior to forearm crutches concerning oxygen cost (P=0.027) but not significantly different from the axillary crutches (P=0.062). DISCUSSION Compared to frequently used orthoses, the developed device provides mobilization using less or similar amount of energy. Additionally it spares one upper extremity to be used for other activities.