Bone metabolic responses to low energy availability achieved by diet or exercise in active eumenorrheic women

Papageoirgiou, Maria and Martin, Daniel and Colgan, Hannah and Cooper, Simon and Greeves, Julie and Tang, Jonathan and Fraser, William and Elliott-Sale, Kirsty and Sale, Craig (2018) Bone metabolic responses to low energy availability achieved by diet or exercise in active eumenorrheic women. Bone, 114 . pp. 181-188. ISSN 8756-3282

Full content URL: https://doi.org/10.1016/j.bone.2018.06.016

Documents
Bone metabolic responses to low energy availability achieved by diet or exercise in active eumenorrheic women
[img]
[Download]
[img]
Preview
PDF (pdf)
Papaegorgiou et al. (2018) Accepted pre-proof.pdf - Whole Document
Available under License Creative Commons Attribution Non-commercial No Derivatives.

778kB
Item Type:Article
Item Status:Live Archive

Abstract

Purpose
We aimed to explore the effects of low energy availability (EA)[15 kcal·kg lean body mass (LBM)−1·d−1] achieved by diet or exercise on bone turnover markers in active, eumenorrheic women.

Methods
By using a crossover design, ten eumenorrheic women (VO2 peak: 48.1 ± 3.3 ml·kg−1·min−1) completed all three, 3-day conditions in a randomised order: controlled EA (CON; 45 kcal·kgLBM−1·d−1), low EA through dietary energy restriction (D-RES; 15 kcal·kgLBM−1·d−1) and low EA through increasing exercise energy expenditure (E-RES; 15 kcal·kgLBM−1·d−1), during the follicular phase of three menstrual cycles. In CON, D-RES and E-RES, participants consumed diets providing 45, 15 and 45 kcal·kgLBM−1·d−1. In E-RES only, participants completed supervised running sessions (129 ± 10 min·d−1) at 70% of their VO2 peak that resulted in an exercise energy expenditure of 30 kcal·kg LBM−1·d−1. Blood samples were collected at baseline (BASE) and at the end of the 3-day period (D6) and analysed for bone turnover markers (β-CTX and P1NP), markers of calcium metabolism (PTH, albumin-adjusted Ca, Mg and PO4) and hormones (IGF-1, T3, insulin, leptin and 17β-oestradiol).

Results
In D-RES, P1NP concentrations at D6 decreased by 17% (BASE: 54.8 ± 12.7 μg·L−1, D6: 45.2 ± 9.3 μg·L−1, P < 0.001, d = 0.91) and were lower than D6 concentrations in CON (D6: 52.5 ± 11.9 μg·L−1, P = 0.001). P1NP did not change significantly in E-RES (BASE: 55.3 ± 14.4 μg·L−1, D6: 50.9 ± 15.8 μg·L−1, P = 0.14). β-CTX concentrations did not change following D-RES (BASE: 0.48 ± 0.18 μg·L−1, D6: 0.55 ± 0.17 μg·L−1) or E-RES (BASE: 0.47 ± 0.24 μg·L−1, D6: 0.49 ± 0.18 μg·L−1) (condition × time interaction effect, P = 0.17). There were no significant differences in P1NP (P = 0.25) or β-CTX (P = 0.13) responses between D-RES and E-RES. Both conditions resulted in reductions in IGF-1 (−13% and − 23% from BASE in D-RES and E-RES, both P < 0.01) and leptin (−59% and − 61% from BASE in D-RES and E-RES, both P < 0.001); T3 decreased in D-RES only (−15% from BASE, P = 0.002) and PO4 concentrations decreased in E-RES only (−9%, P = 0.03).

Conclusions
Low EA achieved through dietary energy restriction resulted in a significant decrease in bone formation but no change in bone resorption, whereas low EA achieved through exercise did not significantly influence bone metabolism. Both low EA conditions elicited significant and similar changes in hormone concentrations.

Keywords:energy availability, dietary energy restriction, exercise energy expenditure, bone metabolism, active eumenorrheic women
Subjects:C Biological Sciences > C600 Sports Science
Divisions:College of Social Science > School of Sport and Exercise Science
Related URLs:
ID Code:32461
Deposited On:21 Jun 2018 22:08

Repository Staff Only: item control page