Cardiovascular Risk and Functional Responses From Dancing at Home in the Elderly With and Without Type 2 Diabetes

Triglycerides, a lipid profile marker, will be analyzed in plasma (after 8h fasting), and measured by enzymatic colorimetric method, using an automated analyzer (Cobas C111, Roche Diagnostics, Basel, Switzerland). Lower triglycerides values correspond to better metabolic health, as follows: Desirable levels: less than 150 (mg/dL). Borderline high: 150 to 199 mg/dL. High: 200 to 499 mg/dL.

Total cholesterol, a lipid profile marker, will be analyzed in plasma (after 8h fasting), and measured by enzymatic colorimetric method, using an automated analyzer (Cobas C111, Roche Diagnostics, Basel, Switzerland). Lower LDL-Cholesterol values correspond to better metabolic health, as follows: Desirable: less than 200 mg/dL. Borderline high: 200-239 mg/dL. High: 240 mg/dL and above.

LDL-Cholesterol levels, a lipid profile marker, will be estimated by Friedewald (1972). Lower LDL-Cholesterol values correspond to better metabolic health, as follows: Desirable: less than 100 mg/dL. Near-desirable: 100-129 mg/dL. Borderline High: 130-159 mg/dL. High: 160-189 mg/dL.

HDL-Cholesterol, a lipid profile marker, will be analyzed in plasma (after 8h fasting), and measured by enzymatic colorimetric method, using an automated analyzer (Cobas C111, Roche Diagnostics, Basel, Switzerland). Higher HDL-Cholesterol values correspond to better metabolic health, as follows: Desirable HDL-Cholesterol values: 45 to 70 mg/dL for men, 50 to 90 mg/dL for women.

Blood fasting glucose levels, a glycemic profile marker, will be analyzed in plasma (after 8h fasting), and measured by enzymatic colorimetric method, using an automated analyzer (Cobas C111, Roche Diagnostics, Basel, Switzerland). Normal values of fasting glycaemia is between 70 and 100 mg/dL for people who do not have diabetes. Fasting blood glucose levels greater than or equal to 126 mg/dL is considered for diagnosis of diabetes.

Fasting insulin, a glycemic profile marker, will be analyzed in plasma (after 8h fasting), and determined by enzyme-linked immunosorbent assay (ELISA), according to manufacturer's instructions. Normal insulin levels are considered superior to 25 mlU/L, or < 174 pmol/L (SI Units: Conversional units x 6.945).

Glycemic profile marker. Homeostatic model of insulin resistance, calculated using fasting values of insulin and glycemia, in accordance with the following formula: fasting insulin (microU/L) x fasting glucose (nmol/L)/22.5.

Changes in Glycemic Responses to Oral Glucose Tolerance Test, used to test glucose tolerance, will be analyzed in plasma (after 8h fasting), by enzymatic colorimetric method, using an automatic analyzer (ROCHE, Cobas C111, Switzerland). Blood glucose will be measured at fasting, 30 min, one hour and two hours, after the ingestion of a drink with 75g of glucose dissolved in water. After two hours, plasma glucose levels (mg/dL) of 139 and below are considered normal. Values in between 140 and 199 correspond to pre-diabetes (impaired glucose tolerance). Values of 200 and above correspond to diabetes mellitus.

CRP, a cardiovascular risk and inflammatory marker, will be analyzed in plasma (after 8h fasting), and determined by enzyme-linked immunosorbent assay (ELISA), according to manufacturer's instructions. High levels of CRP occur when some type of inflammatory or infectious processes is occurring in the bod. High CRP levels may predict a higher risk for cardiovascular disease. Values in between 3.0 to 10.0 mg/L indicate slight inflammation, but origin is unspecific.

TNF-alpha, an inflammatory marker, will be analyzed in serum (after 8h fasting), and determined by enzyme-linked immunosorbent assay (ELISA), according to manufacturer's instructions. Chronically elevated levels of TNF-alpha are linked with an increased risk of autoimmune diseases, obesity, and diabetes, among other diseases characterized by a chronic low-grade inflammation state. The recommended reference range of serum TNF-α vary from non detectable to 8.1 pg/mL.

The maximal isometric and isokinetic knee extension capacity will be measured using an Isokinetic Dynamometer (Cybex Norm, Cybex Norm,Ronkonkoma, New York, USA). The participants will perform 3 sets of 5 s and will be instructed to isometrically produce the maximal knee extension force as fast as possible at 60° of knee flexion (0° represents full extension). After a pre-test of 3 submaximal repetitions for angular velocity familiarization, maximal isokinetic knee extension peak torque will be measured during one set of 4 repetitions at the angular velocity of 60・s-1. The test will be performed in a 90° range of motion Both maximal isometric and isokinetic sets will be performed with 3 min of rest between them.

Participants will perform a jump test using an electronic contact mat system. Jump height will be determined using an acknowledged flight-time calculation. Each participant will be instructed to use maximum effort to perform the double-leg CMJ test. They will be given 3 attempts to obtain their maximum jump height in each test, with 10 s of rest between attempts, with the highest value utilized for subsequent analysis.

For muscle thickness, transversal images of the right vastus lateralis, rectus femoris, vastus intermedius, and vastus medialis muscles will be obtained using a 38-mm, 9.0 megahertz linear-array transducer, with a Nemio XG ultrasound (Toshiba, Japan). The ultrasound muscular images were analysed via ImageJ software (National Institute of Health, USA, version 1.37). The subcutaneous adipose tissue and bone tissue will be identified, and the distance between them will be defined as muscle thickness. Quadriceps femoris muscle thickness will be considered as the sum of the four lower-body muscles muscle thickness. Increases in muscle thickness indicate gains in lean mass, improved body composition, and health and function related factors.

Static balance will be evaluated with the participant in unipedal stance of the dominant leg, with eyes closed. The opposite leg remained in the air, with hip and knee flexed at a 90° angle. The longest duration keeping the position (30s maximum) in three attempts will be recorded (stopwatch), with 2 min break.

The TUG test consist in measuring the time (s) that the participant need to get up from a standard arm chair (43 cm), walk for 3m at usual walking speed, turn, and walk back to sit down. The fastest time in three attempts was recorded, with 2 min break in between them. Times were recorded to the nearest millisecond and transformed in m/s. A TUG score of 13.5 seconds or longer is predictive of reduced dynamic balance and fall risk.

The ability to seat and stand (chair raise test) will be assessed by the time required to rise from sitting five times as fast as possible from a standard chair (43 cm) with the participants folding arms across their chest. Recordings will be made using a stopwatch starting at the initiation of the movement and stopping when subjects stood upright for the 5th time.

The fear of falling will be analyzed by the Falls Efficacy Scale- International Brazil (FES-I-Brazil). This scale evaluates how confident the participant is in performing daily activities. The total score varies from 16 points (not worried at all) to 64 (extremely worried). The cut-off point to discriminate fallers and non fallers is 31 points.

Quality of life will be assessed by the abbreviated version of the World Health Organization Quality of Life (WHOQOL) questionnaire, which is specific for the elderly population. It contains 26 questions in total (2 for general quality of life assessment), and 24 including four domains (physical, psychological, social and environmental). The scores for each question are from 1 (very bad) to 5 (very good) quality of life for each specific domain. Scores 2, 3 and 4 mean bad, neutral and good, respectively. The final score is expressed in percentage (from 0 to 100%). As closer the score is to 100%, higher is the general quality of life of that individual.

The Godin-Shephard leisure-time physical activity questionnaire will be used in its validated version and translated into Brazilian Portuguese. Light, moderate or vigorous physical activities, performed for at least 15 min during leisure time, will be registered by the participants. The frequency is multiplied by the metabolic equivalent (MET). High scores indicate a higher level of physical activity during leisure. For example, in the reference to the score in units using only moderate and strenuous physical activities, 24 units or more means "Active", indicating substantial benefits; from 14 to 23 units means "Moderately active", indicating some benefits; and less than 14 units means "Insufficiently active", indicating low benefits.

The random number generation task evaluates executive functions, particularly inhibition. Briefly, participants verbally generated a random sequence of 100 numbers chosen between one and nine, at a frequency of 40 bpm, paced by a metronome. The randomness of the sequence is elaborated to obtain three indices that were theoreti¬cally related to the inhibitory function: the Turning Point Index, the Adjacency, and the Runs. High levels on the Turning Point Index, but low levels of Adjacency and Runs correspond to a high ability to inhibit the production of stereotyped strings, therefore contributing to the optimal control of complex activities.

The trail making test assesses attention, speed, and cognitive flexibility. The standard protocol used requires participants to draw lines connecting in ascending order and as quickly as possible 25 circles distributed over a sheet of paper. The test has a part A with numbers only and a part B with numbers and letters joined in alternation (i.e, 1-A-2-B-3-C, and so on). A summary score will be calculated by subtracting the time taken in seconds to complete part A from the time at part B (ΔTrail Making) and used for analysis.