Intensity Walking Exercise Research Articles

Gait Recognition and Walking Exercise Intensity Estimation

Cardiovascular patients consult doctors for advice regarding regular exercise, whereas obese patients must self-manage their weight. Because a system for permanently monitoring and tracking patients’ exercise intensities and workouts is necessary, a system for recognizing gait and estimating walking exercise intensity was proposed. For gait recognition analysis, αβ filters were used to improve the recognition of athletic attitude. Furthermore, empirical mode decomposition (EMD) was used to filter the noise of patients’ attitude to acquire the Fourier transform energy spectrum. Linear discriminant analysis was then applied to this energy spectrum for training and recognition. When the gait or motion was recognized, the walking exercise intensity was estimated. In addition, this study addressed the correlation between inertia and exercise intensity by using the residual function of the EMD and quadratic approximation to filter the effect of the baseline drift integral of the acceleration sensor. The increase in the determination coefficient of the regression equation from 0.55 to 0.81 proved that the accuracy of the method for estimating walking exercise intensity proposed by Kurihara was improved in this study.

Prescription of Walking Exercise Intensity from the Incremental Shuttle Walk Test in People with Chronic Obstructive Pulmonary Disease

This study determined the intensity of walking exercise prescribed from 70% of peak speed achieved during the incremental shuttle walk test (ISWT) in people with chronic obstructive pulmonary disease and whether a steady-state response was achieved when exercising at this intensity. Each participant performed lung function tests, an incremental cycle test, two ISWTs, and a 10-min continuous walking exercise at 70% peak ISWT speed. Oxygen consumption (V(O2)) was collected using a portable system (Cosmed K4b(2), Rome, Italy). The V(O2) from the 10-min walking exercise was compared with V(O2)peak from the better ISWT as a measure of walking exercise intensity. Thirty-four participants completed the study. The mean intensity achieved during the 10-min walking exercise was 76% (11%) V(O2)peak. Steady-state V(O2) was achieved by minute 5 in the 10-min walking exercise. Prescription of walking exercise at 70% of the peak ISWT speed provided an intensity appropriate for achieving physiologic training responses.

Exercise induced skeletal muscle metabolic stress is reduced after pulmonary rehabilitation in COPD

In COPD, skeletal muscle ATP resynthesis may be insufficient to meet demand during exercise due to excessive anaerobic and reduced oxidative (mitochondrial) energy production, leading to metabolic stress. We investigated the effect of outpatient pulmonary rehabilitation (PR) on the metabolic response (measured by exercise-induced accumulation of plasma ammonia) and determined whether this response predicted functional improvement following PR. 25 subjects with stable COPD [mean (SD) age 67 (8)years and FEV(1) 47 (18)% predicted] performed maximal cycling ergometry before and after PR. Plasma ammonia was measured at rest, during exercise and 2 min post-exercise. Following PR, there were significant increases in peak cycle WR and ISWT performance (Mean (SEM) changes 13.1 (2.0) W and 93 (15) m respectively, p < 0.001). Mean (SEM) rise in plasma ammonia was reduced at peak (Pre vs Post-PR: 29.0 (4.5) vs 20.2 (2.5) μmol/l, p < 0.05) and isotime (Pre vs Post-PR: 29.0 (4.5) vs 10.6 (1.7) μmol/l, p < 0.001) exercise. Improvements in exercise performance after PR were similar among subgroups who did versus those who did not show a rise in ammonia at baseline. The results suggest that muscle cellular energy production was better matched to the demands of exercise following PR. We conclude that a pragmatic outpatient PR programme involving high intensity walking exercise results in significant adaptation of the skeletal muscle metabolic response with a reduction in exercise-related metabolic stress. However, the outcome of PR could not be predicted from baseline metabolic response.

Effect of Walking Exercise Intensity on leucocyte DNA Telomere Length in Middle-aged Women

Effect of Walking Exercise Intensity on leucocyte DNA Telomere Length in Middle-aged Women

Walking Compared to Nutrition Education Improves Physical Functional Performance in Septuagenarians

The health benefits of moderate aerobic exercise are well documented, however the efficacy of a moderate intensity walking exercise program on functional performance has not been demonstrated in lower socioeconomic older adults. PURPOSE: To evaluate the effect of walking or nutrition education on functional performance with a randomized controlled trial of low socioeconomic older adults. METHODS: Twenty-four older adults with a mean age of 70.4±7.3 years were randomized to a walking (N=12) or nutrition education (NE) group (N=12). Eighty percent of both groups reported an annual income below $20,000. In addition 38% fell below poverty level (<$9570 annually, Leavitt, 2005). An aerobic intensity of 60–75% of maximum heart rate was prescribed to the walking group which met for 1 hour 3x/week for 16-weeks. The NE group received nutrition education presentations every other week for 16-weeks. The primary outcome measures included: aerobic capacity (VO2 peak) and the Continuous Scale Physical Functional Performance 10 (PFP-10). One-way ANOVA was used to evaluate the change over 16-weeks. Significance was set at a p-value of <0.05. RESULTS:TableCONCLUSION: Walking is an inexpensive and effective means to increase physical function in older adults. This is of particular significance in those with limited income.

THE EFFECT OF INTERMITTENT HIGH-INTENSITY RUNNING ON THE RATE OF GASTRIC EMPTYING IN MAN

PURPOSE The aim of this study was to examine the effect of variable-intensity shuttle running exercise on the gastric emptying rate of a carbohydrate-free placebo (P) drink and of a 6.4% carbohydrate-electrolyte (CHO) sports drink. METHOD We compared the volume of test drink emptied in 8 healthy males during two 15 min periods of low intensity walking exercise (WE) and during two 15 min periods of a shuttle running test (LIST) that simulates the activity pattern of soccer. Gastric emptying was measured on the four trials using a modification of the double sampling aspiration technique following ingestion of a body mass adjusted volume of the appropriate test drink. On each trial, subjects ingested 420 ± 49 ml (5 ml/kg) of test drink immediately before starting the first 15 min of exercise and 167 ± 18 ml (2 ml/kg) was ingested before the second exercise bout. RESULTS During the initial 15 min of exercise, the volume of P (124 ± 95 ml) and CHO (71 ± 43 ml) drinks emptied was similar for the two LIST trials, but the volume of P (227 ± 85 ml) and CHO (159 ± 63 ml) drinks emptied on the WE trials was greater than for the respective test drinks on the LIST trials (p < 0.05). Similar volumes of test drinks were emptied on all trials (p = 0.20) during the second 15 min of exercise. Over the 30 min of each trial, the exercise intensity of the LIST reduced the volume of the P (211 ± 108 ml) and CHO (208 ± 83 ml) drink emptied from the stomach compared with that on the WE trial for the P (396 ± 74 ml; p < 0.001) and CHO (293 ± 73 ml; p < 0.05) drink respectively. CONCLUSIONS The data demonstrate that the exercise intensity of the LIST is sufficient to slow gastric emptying of both carbohydrate and non-carbohydrate containing drinks compared to low-intensity walking. Dilute carbohydrate-electrolyte drinks are emptied at about the same rate as carbohydrate-free beverages during variable-intensity running.

Gastric emptying during walking and running: effects of varied exercise intensity.

Gastric emptying is increased during running (50%-70% maximal aerobic uptake, VO2max) as compared to rest. Whether this increase varies as a function of mode (i.e. walking vs running) and intensity of treadmill exercise is unknown. To examine the gastric emptying characteristics of water during treadmill exercise performed over a wide range of intensities relative to resting conditions, 10 men ingested 400 ml of water prior to each of six 15 min exercise bouts or 15 min of seated rest. Three bouts of walking exercise (1.57 m.s-1) were performed at increasing grades eliciting approximately 28%, 41% or 56% of VO2max. On a separate day, three bouts of running (2.68 ms-1) exercise were performed at grades eliciting approximately 57%, 65% or 75% of VO2max. Gastric emptying was increased during treadmill exercise at all intensities excluding 75% VO2max as compared to rest. Gastric emptying was similar for all intensities during walking and at 57% and 65% VO2max during running. However, running at 74% VO2max decreased the volume of original drink emptied as compared to all lower exercise intensities. Stomach secretions were markedly less during running as compared to walking and rest. These data demonstrate that gastric emptying is similarly increased during both moderate intensity (approximately 28%-65% VO2max) walking or running exercise as compared to resting conditions. However, gastric emptying decreases during high intensity exercise. Increases in gastric emptying during moderate intensity treadmill exercise may be related to increases in intragastric pressure brought about by contractile activity of the abdominal muscles.