This file was dowloaded from the institutional repository Brage NIH -brage.bibsys.no/nih Caspersen, C., Berthelsen, A., Eik, M., Pakozdi, C., Kjendlie, P.-L. (2010).Added mass in human swimmers: age and gender differences. Title: Added mass in human swimmers: age and gender differences. AbstractIn unstationary swimming (changing velocity), some of the water around the swimmer is set in motion. This can be thought of as an added mass (Ma) of water. The purpose of this study was to find added mass on human swimmers and investigate the effect of shape and body size. Thirty subjects were connected to a 2.8m long bar with handles, attached with springs (stiffness k=318N/m) and a force cell. By oscillating this system vertically and registering the period of oscillations it was possible to find the added mass of the swimmer, given the known masses of the bar and swimmer.Relative added mass (Ma%) for boys, women and men were, respectively, 26.8±2.9%, 23.6±1.6% and 26.8±2.3% of the subjects total mass. This study reported significantly lower added mass (p<0.001) and relative added mass (p<0.002) for women compared to men, which indicate that the possible body shape differences between genders may be an important factor determining added mass. Boys had significantly lower (p<0.001) added mass than men. When added mass was scaled for body size there were no significant differences (p=0.996) between boys and men, which indicated that body size is an important factor that influences added mass. The added mass in this study seems to be lower and within a smaller range than previously reported (Klauck, 1999;Eik et al., 2008). It is concluded that the added mass in human swimmers, in extended gliding position are approximately ¼ of the subjects' body mass.

This file was dowloaded from the institutional repository Brage NIH -brage.bibsys.no/nih Caspersen, C., Stensrud, T., Thorsen, E. (2011)

This file was dowloaded from the institutional repository Brage NIH -brage.bibsys.no/nih Stang, J., Bråten, V., Caspersen, C., Thorsen, E., Stensrud, T. (2014 1 ABSTRACT Background: Nitric oxide (NO) concentration in exhaled gas is a marker of some inflammatory processes in the lung and endogenous NO plays a role in the physiological responses to exercise and altitude. The aim of this study was to compare changes in exhaled NO concentration 5-60 min after high intensity exercise at 2800 m and at 180 m altitude.

The purpose of this study was to assess immediate changes in the partial pressure of nitric oxide (NO) in exhaled gas (PE NO ) in healthy trained subjects who were acutely exposed to moderate altitude. One group of nine and another group of 20 healthy subjects were exposed to an ambient pressure of 728 hPa (546 mmHg) corresponding to an altitude of 2800 m for 5 and 90 min, respectively, in an altitude chamber. PE NO was measured offline by sampling exhaled gas in tight metal foil bags at 5, 30, 60, and 90 min. A correction for increased expiratory flow rate due to gas density effects at altitude was performed (PE NO corr). PE NO was significantly decreased by 13-16%, while the fraction of NO in exhaled gas (FE NO) was increased by 16-19% compared to sea level. There was no significant change in PE NO corr after exposure to altitude for 5, 30, 60, and 90 min. We conclude that there was no change in PENO upon arrival at altitude after correcting for gas density effects on expiratory flow rate. Corrections for altitude effects must be done before comparing measurements performed at different altitudes when using measurements of FENO to monitor athletes who have asthma during training at altitude.

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