Effect of 5 years of exercise training on the cardiovascular risk profile of older adults: the Generation 100 randomized trial.

AIMS: The aim of this study was to compare the effects of 5 years of supervised exercise training (ExComb), and the differential effects of subgroups of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT), with control on the cardiovascular risk profile in older adults. METHODS AND RESULTS: Older adults aged 70-77 years from Trondheim, Norway (n = 1567, 50% women), able to safely perform exercise training were randomized to 5 years of two weekly sessions of HIIT [∼90% of peak heart rate (HR), n = 400] or MICT (∼70% of peak HR, n = 387), together forming ExComb (n = 787), or control (instructed to follow physical activity recommendations, n = 780). The main outcome was a continuous cardiovascular risk score (CCR), individual cardiovascular risk factors, and peak oxygen uptake (VO2peak). CCR was not significantly lower [-0.19, 99% confidence interval (CI) -0.46 to 0.07] and VO2peak was not significantly higher (0.39 mL/kg/min, 99% CI -0.22 to 1.00) for ExComb vs. control. HIIT showed higher VO2peak (0.76 mL/kg/min, 99% CI 0.02-1.51), but not lower CCR (-0.32, 99% CI -0.64 to 0.01) vs. control. MICT did not show significant differences compared to control or HIIT. Individual risk factors mostly did not show significant between-group differences, with some exceptions for HIIT being better than control. There was no significant effect modification by sex. The number of cardiovascular events was similar across groups. The healthy and fit study sample, and contamination and cross-over between intervention groups, challenged the possibility of detecting between-group differences. CONCLUSIONS: Five years of supervised exercise training in older adults had little effect on cardiovascular risk profile and did not reduce cardiovascular events. REGISTRATION: ClinicalTrials.gov: NCT01666340.

Exercise patterns in older adults instructed to follow moderate- or high-intensity exercise protocol - the generation 100 study.

BACKGROUND: Making older adults exercise and keeping them in exercise programs is a major challenge. Understanding how older adults prefer to exercise may help developing tailored exercise programs and increase sustained exercise participation in ageing populations. We aimed to describe exercise patterns, including frequency, intensity, type, location and social setting of exercise, in older adults instructed to follow continuous moderate-intensity training (MCT) or high-intensity interval training (HIIT) over a one-year period. METHODS: Frequency, intensity, type, location and social setting (alone vs. together with others) of exercise were assessed using exercise logs from 618 older adults (aged 70-77 years) randomized to MCT or HIIT. All participants completed exercise logs after each exercise session they performed during one year. Pearson Chi-square tests were run to assess the association between intensity, type, location and social setting of exercise with training group. RESULTS: Both groups performed 2.2 ± 1.3 exercise sessions per week during the year. Walking was the most common exercise type in both groups, but MCT had a higher proportion of walking sessions than HIIT (54.2% vs. 41.1%, p < 0.01). Compared to MCT, HIIT had a higher proportion of sessions with cycling (14.2% vs. 9.8%, p < 0.01), combined endurance and resistance training (10.3% vs. 7.5%, p < 0.01), jogging (6.5% vs. 3.2%, p < 0.01) and swimming (2.6% vs. 1.7%, p < 0.01). Outdoors was the most common exercise location in both training groups (67.8 and 59.1% of all sessions in MCT and HIIT, respectively). Compared to MCT, HIIT had a higher proportion of sessions at a gym (21.4% vs. 17.5%, p < 0.01) and sports facility (9.8% vs. 7.6%, p < 0.01). Both groups performed an equal amount of sessions alone and together with others, but women had a higher proportion of sessions together with others compared to men (56% vs. 44%, p < 0.01). CONCLUSION: This is the first study that has followed older adults instructed to perform MCT or HIIT over a one-year period, collected data from each exercise session they performed and provided important knowledge about their exercise patterns. This novel information may help researchers and clinicians to develop tailored exercise programs in an ageing population.

Absolute and relative accelerometer thresholds for determining the association between physical activity and metabolic syndrome in the older adults: The Generation-100 study.

BACKGROUND: When assessing population adherence to physical activity (PA) recommendation using accelerometers, absolute intensity threshold definition is applied despite having limited validity in those with low cardiorespiratory fitness (CRF), who are unable to reach them (e.g older adults). Thus, PA thresholds relative to CRF may be an alternative approach. We compared the proportion of the older adults meeting the PA recommendation when PA is assessed using absolute versus sex-and-CRF-adjusted (relative) accelerometer thresholds and determined the association between relative versus absolute moderate PA (MPA), vigorous PA (VPA) and moderate-to-vigorous PA (MVPA) and metabolic syndrome (MetS). METHODS: Cross-sectional study of 509 men and 567 women aged 70-77. Accelerometer assessed MPA, VPA and MVPA were analyzed using absolute and relative thresholds. Meeting the PA-recommendation was defined as amounting ≥150 min/week in MPA/MVPA or 75 min/week in VPA, respectively. CRF was directly measured as peak oxygen uptake (VO2peak). MetS was defined as 3 or more of the following: elevated waist circumference, fasting glucose, hypertension, triglycerides, decreased HDL-cholesterol or diabetes, dyslipidemia or hypertension medication. RESULTS: Higher proportion of the population met the recommendation when PA was assessed with relative compared to absolute thresholds: VPA (72.4% vs. 1.7%) and MVPA (75.2% vs. 33.8%). Logistic regression analysis revealed that men and women not meeting the relative-MVPA or VPA recommendation had higher likelihood of MetS (Men: MVPA OR: 1.59, 95% CI: 1.08-2.33. VPA OR: 1.81, 95%CI: 1.23-2.67 and Women: MVPA OR: 2.12, 95% CI: 1.36-3.31; VPA OR: 1.95, 95% CI: 1.29-2.95), compared to men and women meeting the relative MVPA or VPA recommendation. There was no significant association between MetS and absolute MVPA, MPA or VPA recommendations in the fully adjusted model. CONCLUSIONS: The association between meeting/not meeting the PA recommendation and MetS differed with method. Not meeting relative MVPA and VPA recommendation was associated with significantly higher likelihood for presence of MetS. Since relative intensity is part of the current PA recommendation, it should be considered when assessing population PA and associated health risks in the older adults. TRIAL REGISTRATION: Clinical Trial Registration: NCT01931111 (Date of trial registration: July 19, 2013).

Correlates of Objectively Measured Physical Activity Among Norwegian Older Adults: The Generation 100 Study.

The aim of this study was to identify how demographics, physical activity (PA) history, and environmental and biological correlates are associated with objectively measured PA among older adults. PA was assessed objectively in 850 older adults (70-77 years, 48% females) using the ActiGraph GT3X+ activity monitor. Hierarchical multiple regression analysis was used to identify important PA correlates. The included correlates explained 27.0% of the variance in older adult's PA. Cardiorespiratory fitness (CRF), gender, and season were the most important correlates, explaining 10.1%, 3.9%, and 2.7% of the variance, respectively. PA was positively associated with CRF, females were more physically active than males, and PA increased in warmer months compared with colder months. This is, to our knowledge, the largest study of PA correlates in older adults that has combined objectively measured PA and CRF. Our findings provide new knowledge about how different correlates are associated with PA.

New relative intensity ambulatory accelerometer thresholds for elderly men and women: the Generation 100 study.

BACKGROUND: Public health initiatives world-wide recommend increasing physical activity (PA) to improve health. However, the dose and the intensity of PA producing the most benefit are still debated. Accurate assessment of PA is necessary in order to 1) investigate the dose-response relationship between PA and health, 2) shape the most beneficial public health initiatives and 3) test the effectiveness of such initiatives. Actigraph accelerometer is widely used to objectively assess PA, and the raw data is given in counts per unit time. Count-thresholds for low, moderate and vigorous PA are mostly based on absolute intensity. This leads to largely inadequate PA intensity assessment in a large proportion of the elderly, who due to their declining maximal oxygen uptake (VO2max) cannot reach the moderate/vigorous intensity as defined in absolute terms. To resolve this issue, here we report relative Actigraph intensity-thresholds for the elderly. METHODS: Submaximal-oxygen-uptake, VO2max and maximal heart rate (HRmax) were measured in 111 70-77 year olds, while wearing an Actigraph-GT3X+. Relationship between VO2max percentage (%), counts-per-minute (CPM) and gender (for both the vertical-axis (VA) and vector-magnitude (VM)) and VO2max% and HRmax% was established using a mixed-regression-model. VM-and VA-models were tested against each other to see which model predicts intensity of PA better. RESULTS: VO2max and gender significantly affected number of CPM at different PA intensities (p < 0.05). Therefore, intensity-thresholds were created for both men and women of ranging VO2max values (low, medium, high). VM-model was found to be a better predictor of PA-intensity than VA-model (p < 0.05). Established thresholds for moderate intensity (46-63 % of VO2max) ranged from 669-3367 and 834-4048 CPM and vigorous intensity (64-90 % of VO2max) from 1625-4868 and 2012-5423CPM, for women and men, respectively. Lastly, we used this evidence to derive a formula that predicts customized relative intensity of PA (either VO2max% or HRmax%) using counts-per-minute values as input. CONCLUSION: Intensity-thresholds depend on VO2max, gender and Actigraph-axis. PA intensity-thresholds that take all these factors into account allow for more accurate relative intensity PA assessment in the elderly and will be useful in future PA research. TRIAL REGISTRATION: (ClinicalTrials.gov Identifier: NCT02017847, registered 17. December 2013).

Comparing Free Play and Partly Structured Play in 4-5-Years-Old Children in an Outdoor Playground.

The aim of this study was to compare how the organization of a movement session as partly structured play or free play influenced the physical activity engagement in 4-5 years old pre-schoolers. The partly structured playgroup consisted of 46 children and the free playgroup consisted of 33 children. The playground activities consisted of 10 sessions each lasting 1 h, executed once per week in the period Mars to May 2017 at a specific playground setting. The partly structured playgroup conducted a movement activity session that included a combination of both structured- and free play activities. The free playgroup engaged in unstructured play, only. To detect the intensity of the physical activity each child carried an accelerometer 1 h the first week and last week of the intervention. Results indicate a significant difference in physical activity level between the two groups for the 5-year-old in the favor of the partly structured playgroup. There was a significant difference between the four-and 5-year-old in relation to physical activity level. No significant difference between the activity in March and May for the whole group was found.

Predictors of Dropout in Exercise Trials in Older Adults: The Generation 100 Study.

PURPOSE: Dropout from exercise programs, both in the real world and in research, is a challenge, and more information on dropout predictors is needed for establishing strategies to increase the likelihood of maintaining participants in a prescribed exercise program. The aim of the present study was to determine the dropout rate and its predictors during a 3-yr exercise program in older adults. METHODS: In total, 1514 men and women (mean ± SD age = 72.4 ± 1.9 yr) were included in the present study. Participants were randomized to either a supervised exercise intervention or to follow national guidelines for physical activity (PA). Self-reported demographics (e.g., education), general health, morbidity (e.g., heart disease, memory loss, and psychological distress), smoking, and PA were examined at baseline. Cardiorespiratory fitness (CRF) and grip strength were directly measured at baseline. Dropout rate was evaluated after 1 and 3 yr. Multivariate logistic regression analysis was used to identify dropout predictors. RESULTS: The total dropout rate was 11.0% (n = 166) after 1 yr and 14.9% (n = 225) after 3 yr. Significant predictors of dropout after 1 yr were low education, low grip strength, lower cardiorespiratory fitness, low PA level, and randomization to supervised exercise. The same predictors of dropout were significant after 3 yr, with reduced memory status as an additional predictor. CONCLUSION: This is the largest study to identify dropout predictors in a long-term exercise program in older adults. Our findings provide new and important knowledge about potential risk factors of dropout in long-term exercise programs in older adults.

Do weather changes influence physical activity level among older adults? - The Generation 100 study.

INTRODUCTION: Understanding how individual and environmental factors impact physical activity (PA) level is important when building strategies to improve PA of older adults. No studies have examined how hour-to-hour weather changes influence PA in older adults or how the association between weather and PA eventually is related to cardiorespiratory fitness (CRF) measured as peak oxygen uptake. The aim of this study was therefore to examine how hour-to-hour changes in weather effects hour-to-hour PA in a cohort of Norwegian older adults across CRF levels, gender and seasons. METHODS: PA was assessed objectively in 1219 older adults (70-77 years, 51% females) using the Actigraph GT3X+ accelerometer, and quantified as counts·min-1 (CPM). Weather (Norwegian meteorological Institute) and CRF (MetaMax II) were measured objectively. Panel data analysis added a longitudinal dimension when 110.888 hours of weather- and PA data were analyzed. RESULTS: Older adults had a higher PA level in warmer (597 CPM) than colder months (556 CPM) (p<0.01). Fixed effects regression-models revealed that increasing temperatures (per hour) influenced PA positively in both colder and warmer months (all, p<0.01), with greater influence in fitter vs. less fit participants (p<0.01). In warmer months, increasing precipitation negatively influenced PA in both unfit females and unfit males (p<0.01). In colder months, increasing precipitation positively influenced PA for moderately fit to fit males (p<0.01), but not for females and unfit males. CONCLUSION: To the best of our knowledge, this is the first study to examine the association between weather conditions and objectively-measured-PA among Norwegian older adults. Our findings demonstrates that unfit older adults will be less likely to participate in PA when the weather is unpleasant, compared to those highly fit. The data suggests that the impact of weather should not be ignored when planning public health strategies for increasing PA among older adults.

Are Older Adults Physically Active Enough - A Matter of Assessment Method? The Generation 100 Study.

INTRODUCTION: Physical activity (PA) is beneficial for general health. As a result, adults around the world are recommended to undertake regular PA of either absolute or relative intensity. Traditionally, adherence to PA recommendation is assessed by accelerometers that record absolute intensity thresholds. Since ageing often results in a decrease in cardiorespiratory fitness (CRF), older adults (aged > 65 years) might be more susceptible to not meeting the PA recommendation when measured in absolute terms. The aim of the present study was to compare the adherence to the PA recommendation using both absolute and relative thresholds. Additionally, we aimed to report the reference values for overall PA in a large sample of Norwegian older adults. METHODS: PA was assessed for 7 days using the Actigraph GT3X+ accelerometer in 1219 older adults (624 females) aged 70-77 years. Overall PA was measured as counts per minute (CPM) and steps. Absolute and relative moderate-to-vigorous PA (MVPA) thresholds were applied to quantify adherence to PA recommendation. The relative MVPA thresholds were developed specifically for the Generation 100 population sample. CRF was directly measured as peak oxygen uptake (VO2peak). RESULTS: Proportions meeting PA recommendation were 29% and 71% when utilizing absolute and relative MVPA, respectively. More females met the relative PA recommendation compared to males. Overall PA was higher among the youngest age group. Older adults with medium- and high levels of CRF were more physically active, compared to those with the lowest levels of CRF. CONCLUSION: This is the first study to compare adherence to PA recommendation, using absolute and relative intensity thresholds among older adults. The present study clearly illustrates the consequences of using different methodological approaches to surveillance of PA across age, gender and CRF in a population of older adults.

A randomised controlled study of the long-term effects of exercise training on mortality in elderly people: study protocol for the Generation 100 study.

INTRODUCTION: Epidemiological studies suggest that exercise has a tremendous preventative effect on morbidity and premature death, but these findings need to be confirmed by randomised trials. Generation 100 is a randomised, controlled study where the primary aim is to evaluate the effects of 5 years of exercise training on mortality in an elderly population. METHODS AND ANALYSIS: All men and women born in the years 1936-1942 (n=6966), who were residents of Trondheim, Norway, were invited to participate. Between August 2012 and June 2013, a total of 1567 individuals (790 women) were included and randomised to either 5 years of two weekly sessions of high-intensity training (10 min warm-up followed by 4×4 min intervals at ∼90% of peak heart rate) or, moderate-intensity training (50 min of continuous work at ∼70% of peak heart rate), or to a control group that followed physical activity advice according to national recommendations. Clinical examinations, physical tests and questionnaires will be administered to all participants at baseline, and after 1, 3 and 5 years. Participants will also be followed up by linking to health registries until year 2035. ETHICS AND DISSEMINATION: The study has been conducted according to the SPIRIT statement. All participants signed a written consent form, and the study has been approved by the Regional Committee for Medical Research Ethics, Norway. Projects such as this are warranted in the literature, and we expect that data from this study will result in numerous papers published in world-leading clinical journals; we will also present the results at international and national conferences. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov NCT01666340.