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.

The association of change in peak oxygen uptake with use of psychotropics in community-dwelling older adults - The Generation 100 study.

BACKGROUND: The use of psychotropics is high among the older population and may have detrimental effects on their physical and mental health. Cardiorespiratory fitness (CRF) is a strong and modifiable measure of health and declines with age. We aimed to study the association of change in CRF with use of psychotropics in community-dwelling older adults. METHODS: We analyzed longitudinal data from 1531 older adults from the Generation 100 study, aged 70-77 years at inclusion, and with a permanent address in Trondheim, Norway. Data on objectively measured peak oxygen uptake (VO2peak) were linked with register data from the Norwegian Prescription Database on prescribed psychotropics. The included psychotropics were antidepressants (N06A), antipsychotics (N05A), anxiolytics (N05B), hypnotics and sedatives (N05C), and N03AE (benzodiazepine derivatives). Analyses were done on any psychotropics as one group, and on the following separate groups: antidepressants (N06A), benzodiazepines (N05BA, N05CD, and N03AE), and z-hypnotics (N05CF). Peak oxygen uptake was measured four times over a five-year period and corresponding medication use was measured as defined daily doses (DDD). A random effects estimator was applied to investigate the association of change in VO2peak with the use of psychotropics. RESULTS: We found a statistically significant curvilinear association of change in VO2peak with use of any psychotropics and antidepressants. For VO2peak up to ~ 40 ml/kg/min, each 1 ml/kg/min increase was associated by a 3.3 DDD and 2.5 DDD decrease in use of any psychotropics and antidepressants, respectively. A bottoming-out effect was found and increases in VO2peak above ~ 40 ml/kg/min showed increased use of any psychotropics and antidepressants. However, the association of change in VO2peak with use was stronger for changes in the lower continuum of VO2peak levels and decreased with increasing VO2peak. No statistically significant association of change in VO2peak with use of benzodiazepines and z-hypnotics were found. However, because of a non-randomized design, we cannot rule out the possibility of confounding by indication. CONCLUSIONS: The results of this study show a curvilinear association of change in VO2peak with use of any psychotropics and antidepressants in older adults. This relationship adds a new viewpoint on the adverse effects of psychotropic use and should be considered in interventions and policies aimed at reducing psychotropic medication use among the older 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).

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).

Maximal strength training improves bone mineral density and neuromuscular performance in young adult women.

-Exercise guidelines highlight maximizing bone mass early in life as a strategy to prevent osteoporosis. Which intervention is most effective for this purpose remains unclear. This study investigated the musculoskeletal effects of high acceleration, maximal strength training (MST), in young adult women. Thirty healthy women (22 ± 2 years) were randomly assigned to a training group (TG) and a control group (CG). The TG completed 12 weeks of squat MST, executed at 85-90% of maximal strength 1 repetition maximum (1RM), emphasizing progressive loading and high acceleration in the concentric phase. The CG was encouraged to follow the American College of Sports Medicine's exercise guidelines for skeletal health. Measurements included bone mineral density (BMD) and body composition by dual-energy X-ray absorptiometry, dynamic and isometric rate of force development (RFD), and squat 1RM. Serum levels of type 1 collagen amino-terminal propeptide (P1NP), type 1 collagen C breakdown products (CTX), and sclerostin were analyzed by immunoassays. In the TG, lumbar spine and total hip BMD increased by 2.2 and 1.0%, whereas serum P1NP increased by 26.2%. Dynamic RFD and 1RM improved by 81.7 and 97.7%, and isometric RFD improved by 38% at 100 milliseconds. These improvements were significantly greater than those observed in the CG. Within the CG, dynamic RFD and 1RM increased by 27.2 and 12.9% while no other significant changes occurred. These findings suggest that squat MST may serve as a simple, time-efficient strategy to optimize peak bone mass in early adulthood.

Effect of exercise training for five years on all cause mortality in older adults-the Generation 100 study: randomised controlled trial.

OBJECTIVE: To evaluate the effect of five years of supervised exercise training compared with recommendations for physical activity on mortality in older adults (70-77 years). DESIGN: Randomised controlled trial. SETTING: General population of older adults in Trondheim, Norway. PARTICIPANTS: 1567 of 6966 individuals born between 1936 and 1942. INTERVENTION: Participants were randomised to two sessions weekly of high intensity interval training at about 90% of peak heart rate (HIIT, n=400), moderate intensity continuous training at about 70% of peak heart rate (MICT, n=387), or to follow the national guidelines for physical activity (n=780; control group); all for five years. MAIN OUTCOME MEASURE: All cause mortality. An exploratory hypothesis was that HIIT lowers mortality more than MICT. RESULTS: Mean age of the 1567 participants (790 women) was 72.8 (SD 2.1) years. Overall, 87.5% of participants reported to have overall good health, with 80% reporting medium or high physical activity levels at baseline. All cause mortality did not differ between the control group and combined MICT and HIIT group. When MICT and HIIT were analysed separately, with the control group as reference (observed mortality of 4.7%), an absolute risk reduction of 1.7 percentage points was observed after HIIT (hazard ratio 0.63, 95% confidence interval 0.33 to 1.20) and an absolute increased risk of 1.2 percentage points after MICT (1.24, 0.73 to 2.10). When HIIT was compared with MICT as reference group an absolute risk reduction of 2.9 percentage points was observed (0.51, 0.25 to 1.02) for all cause mortality. Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group. This meant that the controls achieved an exercise dose at an intensity between the MICT and HIIT groups. CONCLUSION: This study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels. However, we observed a lower all cause mortality trend after HIIT compared with controls and MICT. TRIAL REGISTRATION: ClinicalTrials.gov NCT01666340.

Long-term Changes in Depressive Symptoms and Estimated Cardiorespiratory Fitness and Risk of All-Cause Mortality: The Nord-Trøndelag Health Study.

OBJECTIVE: To assess the independent and combined associations of long-term changes in depressive symptoms (DSs) and estimated cardiorespiratory fitness (eCRF) with all-cause mortality. PARTICIPANTS AND METHODS: This is a longitudinal cohort study of 15,217 middle-aged and older individuals attending both the second (from August 15, 1995, through June 18, 1997) and third (from October 3, 2006, through June 25, 2008) health surveys of the Nord-Trøndelag Health Study, Norway, and followed until December 31, 2014. Depressive symptoms were estimated using the validated Hospital Anxiety and Depression Scale, and a validated nonexercise model estimated eCRF. Hazard ratios (HRs) were computed using Cox regression. All-cause mortality was ascertained using the Norwegian Cause of Death Registry. RESULTS: The mean age was 63.3±8.9 years, and 7932 (52.1%) were women. During the follow-up period of 7.1±1.1 years, 1157 participants (7.6%) died. Multivariable-adjusted analyses revealed that persistently low DSs were independently associated with a 28% risk reduction of all-cause mortality (HR, 0.72; 95% CI, 0.56-0.92; P=.008) as compared with persistently high DSs. Persistently high eCRF independently predicted a 26% lower risk of death (HR, 0.76; 95% CI, 0.66-0.88; P<.001) relative to low eCRF. Analyses of changes in DSs and eCRF revealed that persistently high eCRF combined with decreased or persistently low DSs decreased mortality risk by 49% (HR, 0.51; 95% CI, 0.28-0.91; P=.02) and 47% (HR, 0.53; 95% CI, 0.37-0.76, P=.001), respectively. CONCLUSION: Maintaining low DSs and high eCRF was independently associated with a lower risk of all-cause mortality. The lowest mortality risk was observed for persistently high eCRF combined with decreased or persistently low DSs. These results emphasize the effect of preventing DSs and maintaining high CRF on long-term mortality risk, which is potentially important for long-term population health.