Arterial stiffness, body composition and self‑reported physical activity to assess fitness versus fatness

Abstract

Arterial stiffness is associated with both obesity and poor physical fitness. However, recent findings indicate that obese/overweight individuals who are physically fit have similar mortality risks to normal weight individuals. Objective: To determine the associations between body composition, self-reported physical activity and arterial health. Methods: Forty-one participants (18 males, age: 46.6 ± 14.9 years, weight: 74.9 ± 14.8 kg, height: 1.72 ± 0.8 m) underwent body composition (fat and muscle mass), pulse wave velocity (PWV), augmentation index (AIx75), and resting heart rate measurements. Data were grouped according to body composition: normal weight (n=24) vs overweight (n=17), and their self-reported physical activity: Inactive (n=9); active (n=32). Data were further assessed according to: normal weight inactive (n=3), normal weight active (n=21), overweight inactive (n=6) and overweight active (n=11). An unpaired t-test was used to determine the between group differences, and then presented as: mean change, ±90% confidence interval, qualitative interpretation Results: Normal weight participants had less arterial stiffness (PWV: -1, ±0.74m/s-2, very likely slower PWV; AIx75: -13, ±6.2, most likely lower AIx75) and resting heart rates (-4.1, ±5.7bpm, possibly lower) compared to overweight participants. Active participants had more muscle mass (5.1, ±4.9kg, likely more), fat mass (-7.1, ±4.7kg, very likely lower), increased resting heart rate (-12, ±6.2bpm, most likely lower), and lower AIx (-12, ±7.9, very likely lower) compared to inactive participants. Active participants had possibly higher PWV (0.3, ±0.93m/s-2) vs inactive participants. Active participants who were overweight had poorer arterial health (PWV: 1.2, ±0.88m/s-2, very likely faster; AIx75: 11, ±7.2, very likely higher) than those who were active and normal weight. However, being overweight and active was associated with improved fat mass (-5.4, ±4.4kg, likely lower) and better AIx75 (-9.6, ±9.8, likely lower) than being overweight and inactive. Conclusions: Normal weight and physically active participants had the most advantageous arterial stiffness and resting heart rate measures. However, while still elevated compared to their normal weight counterparts, active overweight participants had lower fat mass, resting heart rate and arterial stiffness measures than those who were overweight and inactive. These findings highlight the importance of regular physical activity on health outcomes, particularly in overweight populations.