Impact of frailty, early vascular decline and subclinical cognitive impairment in midlife adults: study protocol of the Toledo Study for Healthy Ageing in middle age.

Life expectancy has increased worldwide alongside a rise in disability prevalence during old age. The impact and interrelationship among the precursors of disability in midlife remain to be better understood. Furthermore, investigating whether lifestyle factors may potentially influence health outcomes and the prognosis of vascular disease could be especially relevant among the middle-aged population, which is a priority subpopulation when prevention is the goal. This is an observational, cross-sectional and population-based study. Participants, between 50 and 55 years old, are randomly selected from the municipality of Toledo (Spain). There are six non-consecutive days for the assessments, providing enough rest between evaluations. Participants perform the interview of the Toledo Study for Healthy Aging. Blood pressure monitoring and a resting electrocardiogram are also recorded. Then, resting peripheral and cerebral vascular measurements along with muscle size and architecture are assessed. Blood and urine samples, and body composition data are collected after an overnight fasting. On a different visit, physical performance and muscle function tests are performed. Additionally, brain magnetic resonance imaging is conducted. And finally, an accelerometer is given to the participants for a week. Frailty is evaluated by Frailty Trait Scale and Fried Frailty Phenotype. This project will shed light on the associations between frailty, early cognitive impairment, and vascular aging during midlife, and on the role that lifestyles play in their development. Lastly, this project will provide meaningful implications for public health strategies aimed at promoting healthy aging in later life.

Relationship of body composition with middle cerebral artery hemodynamic using compositional data analysis: Toledo Study for Healthy Ageing in middle age.

Excess adipose tissue may promote chronic systemic inflammation and oxidative stress, causing endothelial damage. Early evidence indicates that obesity may be associated with poorer cerebral perfusion. The purpose of this study was to examine the relationship between body composition and cerebral hemodynamics. A total of 248 middle-aged adults (50-58 years old; 55% women) underwent a ramp test on a cycle-ergometer until volitional exhaustion. Gas exchange was assessed on a breath-by-breath basis. Mean middle cerebral artery velocity (MCAv) was measured using transcranial Doppler, and pulsatility index (PI) calculated. Body composition was assessed by dual X-ray absorptiometry. Statistical analyses were performed using a compositional data approach including a three-compartment model for body composition (trunk fat mass, extremities fat mass, and fat-free mass). The unadjusted models for the whole sample showed that trunk fat mass relative to other compartments was negatively associated with MCAvrest, MCAvmax, and gain, and positively associated with PImax; extremities fat mass relative to other compartments was positively associated with MCAvrest and MCAvmax, and negatively associated with PImax; and fat-free mass relative to other compartments was positively associated with PImax. These associations were sex-dependent, remaining in the women's subgroup. However, after adjusting for confounders, these associations became non-significant, except for PImax in the whole sample and women's subgroup. These findings suggest a possible association between cerebral hemodynamics and body composition in middle-aged adults, highlighting sex-specific differences. Moreover, our results indicate that higher trunk fat mass relative to other compartments may negatively impact cerebral hemodynamics, reducing MCAv and increasing PImax.

Metabolic equivalents intensity thresholds for physical activity classification in older adults.

BACKGROUND: Although the metabolic equivalents (METs) system is a common procedure to quantify the intensity of physical activity in older adults, it remains unclear whether the conventional METs intensity thresholds (CTs) used for this purpose are appropriate in this population. Therefore, this study aimed (i) to derive overall and fitness-specific METs intensity thresholds in older adults ≥ 60 years old (OATs) expressed both in standard METs (VO2/3.5 mL O2·kg-1·min-1) and older adults METs60+ (VO2/2.7 mL O2·kg-1·min-1), and (ii) to compare them with the CTs. METHODS: A total of 93 subjects were assessed for cardiorespiratory fitness. Graded exercise test protocols using indirect calorimetry were performed to calculate individual VO2max and categorize subjects as "very poor/fair" or "good/superior" fitness. Overall and fitness-specific OATs expressed in standard METs (OATsstandard) and METs60+ (OATs60+) were derived based on the %VO2max and the ventilatory thresholds (VTs) physical intensity categories. RESULTS: Significantly higher VO2max, VO2 at VT1 and VO2 at VT2 (p < 0.001) were obtained in the "good/superior" subgroup compared to the "very poor/fair" fitness subgroup. Accordingly, OATs were approximately 69% higher in individuals with a "good/superior" fitness compared to those with a "very poor/fair" fitness. Furthermore, this study showed that OATsstandard were approximately 21-24% lower than OATs60+, and 10-22% higher OATs were observed when following the VTs intensity categories (heavy-intensity physical activity [HPA] and severe-intensity physical activity [SPA]) compared to the %VO2max categories (moderate-intensity physical activity [MPA] and vigorous-intensity physical activity [VPA]). When compared with the CTs, similar or higher OATsstandard and OATs60+ for MPA, and HPA were obtained compared to the conventional MPA threshold (3.0 METs). Conversely, for VPA and SPA, lower, similar, or higher OATs were obtained depending on the METs derivation approach (OATsstandard or OATs60+) or the intensity categories (VO2max or VTs), compared to the conventional VPA threshold (6.0 METs). CONCLUSIONS: None of the derived OATs were concurrently similar to the CTs, suggesting that fitness-specific METs intensity thresholds adapted to the METs derivation approach should be used in older adults. TRIAL REGISTRATION: FenotipAGING (Non-health-care intervention study), PRO-Training (NCT05619250).

Resting Oxygen Uptake Value of 1 Metabolic Equivalent of Task in Older Adults: A Systematic Review and Descriptive Analysis.

BACKGROUND: It is important for sport scientists and health professionals to have estimative methods for energy demand during different physical activities. The metabolic equivalent of task (MET) provides a feasible approach for classifying activity intensity as a multiple of the resting metabolic rate (RMR). RMR is generally assumed to be 3.5 mL of oxygen per kilogram of body mass per minute (mL O2 kg-1 min-1), a value that has been criticized and considered to be overestimated in the older adult population. However, there has been no comprehensive effort to review available RMR estimations, equivalent to 1 MET, obtained in the older adult population. OBJECTIVE: The aim of this review was to examine the existing evidence reporting measured RMR values in the older adult population and to provide descriptive estimates of 1 MET. METHODS: A systematic review was conducted by searching PubMed, Web of Science, Scopus, CINAHL, SPORTDiscus, and Cochrane Library, from database inception to July 2021. To this end, original research studies assessing RMR in adults ≥ 60 years old using indirect calorimetry and reporting results in mL O2 kg-1 min-1 were sought. RESULTS: Twenty-three eligible studies were identified, including a total of 1091 participants (426 men). All but two studies reported RMR values lower than the conventional 3.5 mL O2 kg-1 min-1. The overall weighted average 1 MET value obtained from all included studies was 2.7 ± 0.6 mL O2 kg-1 min-1; however, when considering best practice studies, this value was 11% lower (2.4 ± 0.3 mL O2 kg-1 min-1). CONCLUSION: Based on the results of this systematic review, we would advise against the application of the standard value of 1 MET (3.5 mL O2 kg-1 min-1) in people ≥ 60 years of age and encourage the direct assessment of RMR using indirect calorimetry while adhering to evidence-based best practice recommendations. When this is not possible, assuming an overall value of 2.7 mL O2 kg-1 min-1 might be reasonable. Systematic review registration: International Prospective Register of Systematic Reviews on 30 September 2020, with registration number CRD42020206440.