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- Svedenhag, Jan, et al.
(author)
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Running on land and in water: comparative exercise physiology
- 1992
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In: Medicine & Science in Sports & Exercise. - 0195-9131 .- 1530-0315. ; 24:10, s. 1155-1160
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Journal article (peer-reviewed)abstract
- The effect of water immersion on cardiorespiratory and blood lactate responses during running was investigated. Wearing a buoyant vest, 10 trained runners (mean age 26 yr) ran in water at four different and specified submaximal loads (target heart rates 115, 130, 145, and 155-160 beats.min-1) and at maximal exercise intensity. Oxygen uptakes (VO2), heart rates, perceived exertion, and blood lactate concentrations were measured. Values were compared with levels obtained during treadmill running. For a given VO2, heart rate was 8-11 beats.min-1 lower during water running than during treadmill running, irrespective of exercise intensity. Both the maximal oxygen uptake (4.03 vs 4.60 1 x min-1) and heart rate (172 vs 188 beats.min-1) were lower during water running. Perceived exertion (legs and breathing) and the respiratory exchange ratio (RER) were higher during submaximal water running than during treadmill running, while ventilation (1 x min-1) was similar. The blood lactate concentrations were consistently higher in water than on the treadmill, both when related to VO2 and to %VO2max. Partly in conformity with earlier cycle ergometer studies, these data suggest that immersion induces acute cardiac adjustments that extend up to the maximal exercise level. Furthermore, both the external hydrostatic load and an altered running technique may add to an increased anaerobic metabolism during supported water running.
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| 2. |
- Holmberg, Hans-Christer, et al.
(author)
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Lung function and oxygen uptake during double poling, running and diagonal skiing in elite cross-country skiers
- 2007
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In: Scandinavian Journal of Medicine and Science in Sports. - : Wiley. - 0905-7188 .- 1600-0838. ; 17:4, s. 437-444
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Journal article (peer-reviewed)abstract
- Arterial desaturation during exercise is common in endurance-trained athletes, a phenomenon often more pronounced when the muscle mass engaged in the exercise is large. With this background, the present study monitored seven international-level cross country skiers performing on a treadmill while running (RUN), double poling (DP; upper body exercise) and diagonal skiing (DIA; arm and leg exercise). Static and dynamic lung function tests were performed and oxygen uptake was measured during submaximal and maximal exercise. Lung function variables (including the diffusion capacity) were only 5-20% higher than reported in sedentary men. Vital capacity was considerably lower than expected from the skiers' maximal oxygen uptake (VO(2max)), but the maximal ventilation followed a linear relationship with VO(2max). None or only a mild desaturation was observed in DP, RUN and DIA. Blood lactate concentration was slightly higher in DIA than in DP but not different from RUN. In DIA, VO(2max) was 6.23 +/- 0.47 L/min (mean +/- SD), which was 3.8% and 13.9% higher than in RUN and DP, respectively, with similar peak heart rates for the three exercise modes. No relationships were present either between the degree of desaturation and pulmonary functions tests, or with peak oxygen uptakes. The low blood lactate accumulation during the exhaustive efforts contributed to the arterial oxygen saturation being mild in spite of the very high oxygen uptake observed in these skiers.
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| 4. |
- Svedenhag, Jan, et al.
(author)
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Individual reference values for 2D echocardiographic measurements. The Stockholm - Umeå Study
- 2015
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In: Clinical Physiology and Functional Imaging. - : Wiley. - 1475-0961 .- 1475-097X. ; 35:4, s. 275-282
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Journal article (peer-reviewed)abstract
- Objectives: Improved reference values for 2D echocardiographic measurements are required, even when more recent echocardiographic technology is employed. In addition, it may be preferable to individualize reference values from age, gender and body characteristics of any subject. Design: A material of 180 healthy subjects was collected and investigated, aiming for an even distribution of sex and age (from 20 to 80years of age; the Stockholm material). For atrial areas, material from another 216 healthy subjects with similar sex and age distribution was added (the Umea material). The 2D measures determined were the left and right ventricular diameters in diastole, the left ventricular diameter in systole, the thickness of septum and posterior wall, the diameters of the aortic root (sinotubular junction) and the left atrium (all in parasternal view), together with the left and right ventricular diameters in diastole and left and right atrial areas in end-systole (apical four-chamber view). The width of the inferior vena cava (from subcostal view) was also determined. Results: Confidence intervals for females and males are presented for each of these measures. Multiple linear regression analyses with age, sex and measures of body characteristics as predictors were also performed, and for eight of the 12 measurements, such equations are presented. Conclusions: It is possible to obtain more highly individualized reference values for these cardiac dimensions, which may clinically be a better way of distinguishing pathological states from normal states.
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