Phase angle is associated with the physical fitness of HIV-infected children and adolescents.

Abstract

The objective of this study was to identify the association of phase angle with physical fitness in children and adolescents infected with HIV. Sixty-four children and adolescents infected with HIV (8-15years old) were tested for vertical transmission. The electrical bioimpedance was used to obtain the phase angle. Body fat (BF) and lean soft tissue mass (LSTM) were measured by x-ray absorptiometry, and the manual grip strength was evaluated by dynamometry. The peak oxygen consumption (VO2 peak) was measured by respiratory change in a submaximal incremental test. Moderate-vigorous physical activity (MVP) and sedentary behavior were measured using accelerometers and were used as covariates. Multiple linear regression was used. The linear correlation analyses demonstrated that the phase angle was inversely proportional to relative BF (r=-0.26), but was not associated with absolute body fat (r=-0.02). The phase angle was directly associated with LSTM (r=0.57), handgrip strength, and (r=0.43) peak VO2 (r=0.55). The phase angle was not associated with absolute BF (β=-0.017, P=0.413) and relative (β=-0.014, P=0.175). The phase angle presented a direct association with LSTM (β=0.041, P=0.019) and peak VO2 (β=0.005; P=0.019), regardless of age, sex, sexual maturation, MVPA, sedentary behavior, antiretroviral drugs, and viral load. No association was found between phase angle and handgrip strength (β=0.153; P=0.199). It was concluded that phase angle was associated with LSTM and the aerobic fitness in HIV-infected children and adolescents.