Cardiovascular Risk and Functional Responses From Dancing at Home Compared With Walking in Elderly Individuals With and Without Type 2 Diabetes Mellitus: A Randomized Controlled Trial.

The aging process is characterized by a loss of lean mass simultaneously to an increase in visceral adipose tissue (Bruseghini P. et al. 2015). This may result in reduced glucose uptake and increased levels of pro inflammatory cytokines, which leads to a chronic low grade inflammation state, insulin resistance, type 2 diabetes mellitus (T2DM) and elevated cardiovascular risk (CVR) (Krause, M.S. et al. 2013). Reductions in lean mass are also associated with reductions in muscle strength and power, inducing functional declines that result in difficulties to perform daily activities, and eventual loss of physical independence (Cadore, E.L. and Izquierdo, M. 2013) Costs with the treatment of aging-associated comorbidities are elevated for the health systems (Bielemann, R.M.K. et al. 2010). Searching for low cost strategies of prevention, with long term results, is essential then, especially the ones which may prevent dependence in a large spectrum (at the physical, social and cognitive levels), such as dancing (Laddu, D.R. et al 2020). Particularly, due to the pandemic of Corona Virus Disease-19 (COVID-19), long periods of self-isolation and social distancing have resulted in dramatic changes in the lifestyle of this population, beyond the risk of viral infection (Laddu, D.R. et al 2020). In this context, regular physical activity is considered to be a preventive strategy against chronic diseases due to its beneficial effects on global health (physical, mental, and social domains) (Fletcher, G.F. et.al. 2018). Particularly, dancing has been suggested as a strategy to increase levels of physical activity during quarantine periods (Jiménez-Pavón, D. et al. 2020), considering they can be adjusted for different ages, physical limitations, and levels of previous experience (Rodrigues-Krause, J.C. et al. 2019).

Therefore, the goal of this randomized controlled trial is to investigate the effects of a dance intervention on cardiovascular risk factors and functional capacity of older people, with and without type 2 diabetes mellitus (T2DM), comparing dancing to an active control group of walking exercise. The participants will include men and women between 65 and 80 years old, with body mass index inferior to 35 Kg /m2 and independent for performing daily activities. They should not be engaged in any type of regular physical activity in the past 6 months. Exclusion criteria will include cardiovascular complications, mobility limitations and neurodegenerative diseases.

The experimental design will include 3 parts: 1) Pre-intervention assessments: medical evaluation, fasting blood exams, maximum exercise test, assessments of body composition, balance, gate ability, muscular strength and power. 2) Control Period: 4 weeks for the follow up of the maintenance or changes in the primary and secondary outcomes responses of the participants. Primary and secondary outcomes will be evaluated before and after the control period. 3) Period of interventions: patients will be randomized in blocks (randomization.com), in accordance to their VO2peak, gender, and the presence of T2DM, to one of the two groups: dance or walking. The duration of the dance and walking interventions will be 12 weeks, including 3 sessions per week, each lasting 60 min. performed at home, guided by an expertise instructor, as live online sessions. Session will include several styles (salsa, jazz, aerobics), basic technical elements, no partner required. Walking: performed as a continuous aerobic exercise, outside, at a self-selected intensity, with no simultaneous supervision. Both interventions will include a warm-up (10 min), main part (40 min) and cool-down (10 min). All participants will complete an exercise diary after each exercise session (reporting perception of subjective effort, affective responses, and others). 3) Post-intervention assessments: the same protocols of testing of the pre-interventions assessments will be repeated. 4) Follow-up assessments: participants will be evaluated in 12 weeks times, for primary and secondary outcomes, after the end of the exercise intervention period.

The main outcome of this study is the peak oxygen consumption (VO2peak), as it has been associated with both, cardiovascular risk and functional performance in aging individuals. The secondary outcomes are: (1) cardiovascular risk associated factors: C-reactive protein, TNF-alpha, triglycerides, total cholesterol, LDL-cholesterol, HDL-cholesterol, fasting glucose and insulin, and homeostatic model assessment of insulin resistance (HOMA-IR). (2) Functional performance: muscle strength and power, balance, gate ability and muscle quality. (3) Cognitive function: executive function (random number generation and trial making test). In the following outcomes description of this Clinical Trials record, protocols of assessment for outcomes 1 to 20 are based on Rodrigues-Krause, J.C. et al. 2018. For outcomes 21 and 22 the reference is Forte, R. et al. 2013.

Results will be expressed in mean and confidence interval. All the assessments will be held at the Laboratory of Research in Exercise (LAPEX-UFRGS). Statistics: Generalized estimating equations, followed by the post hoc of least significant difference (LSD) (p<0.05). Comparisons before and after the interventions will be made among groups 1=dancing, 2=dancing T2DM, 3=walking, 4=walking T2DM.