Moderate aerobic exercise (brisk walking) increases bone density in cART‐treated persons
Authors: Bonato M , Bossolasco S , Galli L , Pavei G , Testa M , Bertocchi C , Galvano E , Balconi G , Lazzarin A , Merati G , La Torre A , Cinque P 
Published: November 2012

Moderate intensity aerobic activity reduces the risk of cardiovascular disease, diabetes and metabolic syndrome in the general population and has a potential in preventing bone loss. We evaluated the effects of brisk walking, with or without strength exercise, on bone mineral density in HIV‐infected treated persons. Twenty‐eight HIV‐infected, cART‐treated, sedentary subjects with VL<50 c/mL were enrolled in a 12‐week exercise program, consisting of 3 outdoor sessions/week of 60 min walking at 67–70% of HR (heart rate) max±30 min circuit training at 65% of 1‐RM (repetition maximum). Subjects were examined at baseline (BL) and 12 weeks (W12) by 6‐minute walking test (6MWT) and by counting the number of repetitions for each strength exercise; and by dual energy X‐ray absorptiometry (DEXA) to evaluate lumbar spine and femoral bone mineral density with t‐ and z‐scores ‐ in addition to morphometric (BMI, waist, hip and leg circumference) and blood examination (cytometry, fasting total, HDL and LDL cholesterol, triglycerides, glucose, insulin; AST/ALT, ALP, gGT, creatinine, CPK, HbA1c; CD4+ and CD8+, plasma HIV‐RNA). Differences over time were tested by Wilcoxon‐signed rank test and between groups by Mann‐Whitney test. Twenty‐seven (96%) participants (19M, 8F; median 48 y‐o, IQR 43–54; median CD4+624/µL, IQR 478–708; ART with PI: 13 patients, with NNRTI: 7 patients, and including TDF: 15 patients) completed the 12‐week program with a median adherence of 61% (IQR 50–70): 18 in the ‘walk only’ only group and 9 in the ‘walk and strength’ group. At W12, participants showed significant improvement of distance by 6MWT (Table), and of performance in all strength exercises (crunch p=0.023, lat machine p=0.016, chest press p=0.016, leg extension p=0.016, sitting calf p=0.008, leg press p=0.016). DEXA spine z‐score improved significantly in the whole group, and femoral z‐scores in the ‘walk only’ group. There was no z‐score difference at BL between patients with/out PIs, NNRTIs or TDF. However, spine z‐score improved significantly in patients receiving TDF. At W12 BMI, waist circumference, and LDL also improved significantly in the whole group, whereas no significant changes were observed for the other variables, The above 12‐week program improved fitness and bone density in HIV‐infected treated subjects, in addition to some morphometric variables and serum LDL. Brisk walking, with or without strength exercise, might help control the long‐term consequences of cART.

BL‐median (IQR)
W12‐median (IQR)
p

Distance at 6MWT (m)
658 (605–691)
715 (IQR 690–830)
<0.0001

DEXA spine (z‐score)
−1.15 (−1.7/−0.7)
−1.05 (−1.4/−0.3)
0.002

DEXA spine (z‐score)(TDF‐treated pts)
−1.4 (−1.7/−0.7)
−1.3 (−1.55/−0.5)
0.002

DEXA femoral neck (z‐score)(walk only)
−0.8 (−1.4/−0.2)
−0.5 (−1.2/−0.2)
0.047

DEXA femoral ward (z‐score)(walk only)
−1 (−1.9/−0.6)
−0.75 (−1.4/−0.2)
0.004

BMI
25.7 (24.6–26.3)
24.9 (21.4−26)
0.0016

Waist circumference (cm)
93 (87−100)
92 (85.5−98.5)
0.029

LDL cholesterol (mg/dL)
126 (113−154.5)
116 (96–137.5)
0.0003