In a Journal of Bone and Mineral Research study of older adults with obesity who were cutting calories, an intervention that incorporated resistance training, aerobic training, or neither did not prevent bone loss associated with active weight loss.

The objective of this study was to determine the ability of either aerobic or resistance training to counter the weight?loss?associated bone loss in older adults. There were 187 older adults (67 years, 70% women, 64% white) with obesity (BMI = 34.5 ± 3.7 kg/m2) and cardiovascular disease and metabolic syndrome who were randomized to participate in an 18?month, community?based trial, with a follow?up assessment at 30 months.

Intervention arms included: weight loss alone (WL; 7% to 10% baseline weight), WL plus aerobic training (WL + AT), and WL plus resistance training (WL + RT), as well as DXA?acquired total hip, femoral neck, and lumbar spine areal bone mineral density (aBMD), and trabecular bone score (TBS).

Biomarkers of bone turnover

Biomarkers of bone turnover (procollagen type 1 N?terminal propeptide, C?terminal telopeptide of type 1 collagen) were measured at baseline, 6, 18, and 30 (aBMD and TBS only) months.

CT?acquired hip and spine volumetric BMD (vBMD), cortical thickness, and bone strength were measured in a subset at baseline (n = 55) and 18 months. Total hip aBMD was reduced by 2% in all groups at 18 months, with a primary analysis showing no significant treatment effects for any DXA, biomarker, or CT outcome.

After adjustment for WL and follow?up at 30 months, secondary analyses revealed that total hip [−0.018 (−0.023 to −0.012) g/cm2versus −0.025 (−0.031 to −0.019) g/cm2p = 0.05] and femoral neck [−0.01 (−0.009 to 0.008) g/cm2 versus −0.011 (−0.020 to −0.002) g/cm2p = 0.06] aBMD estimates were modestly attenuated in the WL + RT group compared with the WL group.

Additionally, lumbar spine aBMD was increased in the WL [0.015 (0.007 to 0.024) g/cm2] and the WL + RT [0.009 (0.000 to 0.017) g/cm2] groups compared with the WL + AT [−0.003 (−0.012 to 0.005)g/cm2] group; both p ≤ 0.01.

Community?based exercise does not prevent bone loss during active WL in older adults; however, adding RT may help minimize long?term hip bone loss. 2018 American Society for Bone and Mineral Research. The study's results suggested that resistance training may help minimize long-term hip bone loss, however.

"If minimizing bone loss during active weight loss proves necessary to offset long-term skeletal fragility, then our results suggest that resistance exercise may need to be coupled with other intervention strategies to maximize skeletal benefit," said lead author Dr. Kristen Beavers, of Wake Forest University.

Additional research should seek to elucidate the mechanisms underlying weight-loss-induced bone loss, so that, safe and effective strategies can be designed to preserve all aspects of bone health in dieting older individuals.