Showing papers by "Ulf Ekelund published in 2003"

International physical activity questionnaire: 12-country reliability and validity

Abstract: CRAIG, C. L., A. L. MARSHALL, M. SJOSTROM, A. E. BAUMAN, M. L. BOOTH, B. E. AINSWORTH, M. PRATT, U. EKELUND, A. YNGVE, J. F. SALLIS, and P. OJA. International Physical Activity Questionnaire: 12-Country Reliability and Validity. Med. Sci. Sports Exerc., Vol. 35, No. 8, pp. 1381-1395, 2003. Background: Physical inactivity is a global concern, but diverse physical activity measures in use prevent international comparisons. The International Physical Activity Questionnaire (IPAQ) was developed as an instrument for cross-national monitoring of physical activity and inactivity. Methods: Between 1997 and 1998, an International Consensus Group developed four long and four short forms of the IPAQ instruments (administered by telephone interview or self-administration, with two alternate reference periods, either the "last 7 d" or a "usual week" of recalled physical activity). During 2000, 14 centers from 12 countries collected reliability and/or validity data on at least two of the eight IPAQ instruments. Test-retest repeatability was assessed within the same week. Concurrent (inter-method) validity was assessed at the same administration, and criterion IPAQ validity was assessed against the CSA (now MTI) accelerometer. Spearman's correlation coefficients are reported, based on the total reported physical activity. Results: Overall, the IPAQ questionnaires produced repeatable data (Spearman's clustered around 0.8), with comparable data from short and long forms. Criterion validity had a median of about 0.30, which was comparable to most other self-report validation studies. The "usual week" and "last 7 d" reference periods performed similarly, and the reliability of telephone administration was similar to the self-administered mode. Conclusions: The IPAQ instruments have acceptable measurement properties, at least as good as other established self-reports. Considering the diverse samples in this study, IPAQ has reasonable measurement properties for monitoring population levels of physical activity among 18- to 65-yr-old adults in diverse settings. The short IPAQ form "last 7 d recall" is recommended for national monitoring and the long form for research requiring more detailed assessment. Key Words: MEASUREMENT, SURVEILLANCE, EPIDEMIOLOGY

Effect of monitor placement and of activity setting on the MTI accelerometer output.

Abstract: PURPOSE: To examine the effect of monitor placement (hip vs back) and of activity setting (treadmill vs track) on the output from the Manufacturing Technology Inc. (MTI), activity monitor (model WA ...

Is the ArteACC index a valid indicator of free-living physical activity in adolescents?

Abstract: EKELUND, ULF, JAN AMAN, AND KLAAS WESTERTERP Is the ArteACC index a valid indicator of free-living physical activity in adolescents? Obes Res 2003; 11:793-801 Objective: The principal aim of this study was to validate a proposed new index of physical activity, the activity-related time equivalent based on accelerometry (ArteACC), in adolescents A secondary aim was to develop regression equations for prediction of total energy expenditure (TEE) and activity energy expenditure [AEE 09 TEE resting metabolic rate (RMR)] Research Methods and Procedures: RMR and energy expenditure (EE) under standardized exercises were measured by indirect calorimetry in 36 adolescents (14 to 19 years old) TEE was measured by the doubly labeled water method, and physical activity was assessed simultaneously with an accelerometer for 14 days AEE, AEE in relation to body weight (AEE per kilogram), and activity-related time equivalent based on energy expenditure (ArteEE AEE/ [EE reference activity RMR]) were calculated from laboratory and free-living EE data ArteACC was calculated as total activity counts/activity counts of reference activity Results: ArteACC was significantly related to AEE per kilogram (r 057; p 00001) and ArteEE (r 068; p 0001) The absolute amount of time (minutes per day) spent in physical activity was significantly lower when calculated from ArteACC than from ArteEE (p 0001) TEE was significantly influenced by RMR, sex, and ArteACC (r 2 089) AEE was significantly influenced by sex and ArteACC (r 2 059) Discussion: Despite an absolute difference between the two indexes, ArteEE and ArteACC, ArteACC seems to be a valid indicator of free-living physical activity It contributed significantly, by 33% and 125%, to the explained variations in TEE and AEE, respectively

The European Youth Heart Survey (EYHS): an international study that addresses the multi-dimensional issues of CVD risk factors.

Abstract: The European Youth Heart Survey (EYHS) : an international study that addresses the multi-dimensional issues of CVD risk factors

Endogenous Nitric Oxide Reduces Microvascular Permeability and Tissue Oedema during Exercise in Cat Skeletal Muscle

Abstract: Based on a proposed increase in the release of the vasodilators nitric oxide (NO) and prostacyclin during exercise, and the fact that these substances have vascular permeability-reducing properties, this study was designed to evaluate (1) possible effects of exercise on hydraulic permeability, (2) whether permeability and muscle swelling are reduced by an increased release of NO and prostacyclin during exercise and (3) whether NO and prostacyclin are involved in exercise hyperaemia. The study was performed on an autoperfused cat calf muscle preparation with ligated lymph vessels, and exercise was induced by somatomotor nerve stimulation. Change in microvascular hydraulic permeability was estimated by a capillary filtration coefficient (CFC) technique. We found that the marked muscle volume increase after the start of the exercise gradually decreased, reaching an isovolumetric state within 25 min where CFC had decreased by about 25% (p < 0.05). CFC recovered completely after exercise was stopped. The decrease in CFC was abolished during blockade of endogenous NO by the NO synthase inhibitor L-NAME, but was preserved during blockade of endogenous prostacyclin by tranylcypromine. The muscle volume increase during exercise was about 60% greater with L-NAME than during vehicle or tranylcypromine (p < 0.01). Neither L-NAME nor tranylcypromine had any effect on exercise hyperaemia. We conclude that microvascular hydraulic permeability is reduced during exercise, that this effect reduces exercise-induced muscle swelling, and that the effects are mediated via release of NO. NO and prostacyclin are not involved in exercise hyperaemia.

Nitric oxide and prostacyclin play a role in the regulation of microvascular protein and hydraulic permeability in cat skeletal muscle.

Abstract: Objective:To evaluate a possible role of nitric oxide (NO) and prostacyclin in the regulation of basal microvascular protein and hydraulic permeability. Methods:The study was performed on the autoperfused cat calf muscle. Changes in the osmotic reflection coefficient for albumin, calculated from the extended Starling equation, were used as a measure of altered protein permeability, whereas changes in capillary filtration coefficient (CFC) were used as a measure of altered hydraulic permeability. Results:Inhibition of the endogenous NO production with L-nitro-arginine methyl ester given intra-arterially to the muscle decreased the reflection coefficient to 70% of the control (p< 0.05) and increased the CFC by 17% (p< 0.05). The addition of a simultaneous intra-arterial infusion of the NO precursor Larginine restored both the reflection coefficient and the CFC back to control level. Blockade of the endogenous prostacyclin production with tranylcypromine given intra-arterially decreased the reflection coeffi...

The European Youth Heart Survey (EYHS) : an international study that addresses the multidimensional issues of CVD risk factors

Abstract: The European Youth Heart Survey (EYHS) : an international study that addresses the multidimensional issues of CVD risk factors