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- Norha, Jooa, et al.
(författare)
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Effects of reducing sedentary behavior on cardiorespiratory fitness in adults with metabolic syndrome : A 6-month RCT
- 2023
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Ingår i: Scandinavian Journal of Medicine and Science in Sports. - Chichester : Wiley-Blackwell Publishing Inc.. - 0905-7188 .- 1600-0838. ; 33:8, s. 1452-1461
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Tidskriftsartikel (refereegranskat)abstract
- Introduction:Poor cardiorespiratory fitness (CRF) is associated with adverse health outcomes. Previous observational and cross-sectional studies have suggested that reducing sedentary behavior (SB) might improve CRF. Therefore, we investigated the effects of a 6-month intervention of reducing SB on CRF in 64 sedentary inactive adults with metabolic syndrome in a non-blind randomized controlled trial.Materials and Methods:In the intervention group (INT, n = 33), the aim was to reduce SB by 1 h/day for 6 months without increasing exercise training. Control group (CON, n = 31) was instructed to maintain their habitual SB and physical activity. Maximal oxygen uptake (VO2max) was measured by maximal graded bicycle ergometer test with respiratory gas measurements. Physical activity and SB were measured during the whole intervention using accelerometers.Results:Reduction in SB did not improve VO2max statistically significantly (group × time p > 0.05). Maximal absolute power output (Wmax) did not improve significantly but increased in INT compared to CON when scaled to fat free mass (FFM) (at 6 months INT 1.54 [95% CI: 1.41, 1.67] vs. CON 1.45 [1.32, 1.59] Wmax/kgFFM, p = 0.036). Finally, the changes in daily step count correlated positively with the changes in VO2max scaled to body mass and FFM (r = 0.31 and 0.30, respectively, p < 0.05).Discussion:Reducing SB without adding exercise training does not seem to improve VO2max in adults with metabolic syndrome. However, succeeding in increasing daily step count may increase VO2max. © 2023 The Authors. Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.
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| 2. |
- Sjöros, Tanja, et al.
(författare)
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Both sedentary time and physical activity are associated with cardiometabolic health in overweight adults in a 1 month accelerometer measurement
- 2020
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Ingår i: Scientific Reports. - London : Nature Publishing Group. - 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to examine the associations of cardiometabolic health markers with device-measured sedentary behavior (SB) duration and different intensities of physical activity (PA) among overweight working-aged adults with low self-reported PA levels. This cross-sectional analysis included 144 subjects (42 men) with mean age of 57 (SD 6.5) years and mean BMI of 31.7 (SD 4) kg/m2. SB and standing time, breaks in sedentary time, light PA (LPA) and moderate-to-vigorous PA (MVPA) were measured for 4 consecutive weeks (mean 25 days, SD 4) with hip-worn accelerometers. Fasting plasma glucose, insulin, HbA1c, triglycerides and total cholesterol, HDL and LDL were measured from venous blood samples. HOMA-IR index was calculated as a surrogate of insulin resistance. The associations were examined using linear models. LPA, MVPA, and daily steps associated with better insulin sensitivity and favorable plasma lipid profile, when adjusted for age, sex and BMI, whereas greater proportion of SB associated with insulin resistance and unfavorable lipid profile. As all PA intensities associated with better cardiometabolic health, the total daily duration of PA may be more relevant than intensity in maintaining metabolic health in overweight adults, if the current guidelines for PA are not met.Trial Registration: ClinicalTrials.gov NCT03101228, registered 05/04/2017, https://clinicaltrials.gov/show/NCT03101228 .
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| 3. |
- Sjöros, Tanja, et al.
(författare)
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Influence of the Duration and Timing of Data Collection on Accelerometer-Measured Physical Activity, Sedentary Time and Associated Insulin Resistance
- 2021
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Ingår i: International Journal of Environmental Research and Public Health. - Basel : MDPI AG. - 1661-7827 .- 1660-4601. ; 18:9
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Tidskriftsartikel (refereegranskat)abstract
- Accelerometry is a commonly used method to determine physical activity in clinical studies, but the duration and timing of measurement have seldom been addressed. We aimed to evaluate possible changes in the measured outcomes and associations with insulin resistance during four weeks of accelerometry data collection. This study included 143 participants (median age of 59 (IQR9) years; mean BMI of 30.7 (SD4) kg/m2; 41 men). Sedentary and standing time, breaks in sedentary time, and different intensities of physical activity were measured with hip-worn accelerometers. Differences in the accelerometer-based results between weeks 1, 2, 3 and 4 were analyzed by mixed models, differences during winter and summer by two-way ANOVA, and the associations between insulin resistance and cumulative means of accelerometer results during weeks 1 to 4 by linear models. Mean accelerometry duration was 24 (SD3) days. Sedentary time decreased after three weeks of measurement. More physical activity was measured during summer compared to winter. The associations between insulin resistance and sedentary behavior and light physical activity were non-significant after the first week of measurement, but the associations turned significant in two to three weeks. If the purpose of data collection is to reveal associations between accelerometer-measured outcomes and tenuous health outcomes, such as insulin sensitivity, data collection for at least three weeks may be needed © 2021 by the author. Licensee MDPI, Basel, Switzerland.
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| 4. |
- Sjöros, Tanja, et al.
(författare)
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The effects of a 6-month intervention aimed to reduce sedentary time on skeletal muscle insulin sensitivity : a randomized controlled trial
- 2023
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Ingår i: American Journal of Physiology. Endocrinology and Metabolism. - Rockville, MD : American Physiological Society. - 0193-1849 .- 1522-1555. ; 325:2, s. E152-E162
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Tidskriftsartikel (refereegranskat)abstract
- Sedentary behavior (SB) and physical inactivity associate with impaired insulin sensitivity. We investigated whether an intervention aimed at a 1-h reduction in daily SB during 6 mo would improve insulin sensitivity in the weight-bearing thigh muscles. Forty-four sedentary inactive adults [mean age 58 (SD 7) yr; 43% men] with metabolic syndrome were randomized into intervention and control groups. The individualized behavioral intervention was supported by an interactive accelerometer and a mobile application. SB, measured with hip-worn accelerometers in 6-s intervals throughout the 6-mo intervention, decreased by 51 (95% CI 22-80) min/day and physical activity (PA) increased by 37 (95% CI 18-55) min/day in the intervention group with nonsignificant changes in these outcomes in the control group. Insulin sensitivity in the whole body and in the quadriceps femoris and hamstring muscles, measured with hyperinsulinemic-euglycemic clamp combined with [18F]fluoro-deoxy-glucose PET, did not significantly change during the intervention in either group. However, the changes in hamstring and whole body insulin sensitivity correlated inversely with the change in SB and positively with the changes in moderate-to-vigorous PA and daily steps. In conclusion, these results suggest that the more the participants were able to reduce their SB, the more their individual insulin sensitivity increased in the whole body and in the hamstring muscles but not in quadriceps femoris. However, according to our primary randomized controlled trial results, this kind of behavioral interventions targeted to reduce sedentariness may not be effective in increasing skeletal muscle and whole body insulin sensitivity in people with metabolic syndrome at the population level.NEW & NOTEWORTHY Aiming to reduce daily SB by 1 h/day had no impact on skeletal muscle insulin sensitivity in the weight-bearing thigh muscles. However, successfully reducing SB may increase insulin sensitivity in the postural hamstring muscles. This emphasizes the importance of both reducing SB and increasing moderate-to-vigorous physical activity to improve insulin sensitivity in functionally different muscles of the body and thus induce a more comprehensive change in insulin sensitivity in the whole body.
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