Article - A 2-yr Randomized Controlled Trial on Creatine Supplementation during Exercise for Postmenopausal Bone Health.

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Take home message

Creatine supplementation may have beneficial effects on bone geometry at the proximal femur when combined with a resistance training program and walking programme in postmenopausal women.

Evidence category

A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)

Summary review

Introduction

This study aimed to determine the effects of creatine monohydrate supplementation and exercise on femoral neck bone mineral density (BMD), lumbar spine BMD and proximal femur geometric properties in postmenopausal women over 2 years.

Methods

237 postmenopausal women (mean age, 59 yr) were randomised into 2 groups across 2 sites.
Participant inclusion criteria: no menstrual period for 2 years, and considered at “low” and “moderate” risk of fracture.
Treatment group (n=120) received creatine monohydrate (0.14 g/kg−1 per day−1 mixed with 0.14 g·kg−1·d−1 maltodextrin) and supervised resistance training plus partially supervised walking.
Placebo group (n=117) received 0.28 g·kg−1·d−1 maltodextrin and supervised resistance training plus partially supervised walking.
All participants also received 500 mg of calcium and 10 μg (400 IU) of vitamin D per day.
Resistance exercises and 20-30 mins of brisk walking were performed in-lab and supervised 3 days per week. 3 days of non- supervised 20-30 mins of brisk walking was undertaken outside of the lab.

Results

Creatine monohydrate supplementation combined with resistance training and walking over 2 yr: i) had no effect on BMD at the femoral neck (P < 0.0001), total hip (P < 0.0001), or lumbar spine (P= 0.003); ii) increased lean tissue mass compared with placebo (P = 0.046); iii) preserved a number of geometric properties and may therefore help to maintain bone bending strength and cortical bending under compressive loads.
The authors speculated that creatine supplementation stimulates remodeling of bone to alter geometric properties and whether bone formation or resorption predominates depends on the location of bone in the proximal femur.

Conclusion

2 years of creatine supplementation with resistance training and walking in postmenopausal women had no beneficial effects on BMD but did improve the proximal femur cortical thickness and section modulus bone geometry, and reduced SPW and buckling ratio that may be protective against hip fracture.

Adverse Events: The dose of creatine over 2 years resulted in minimal adverse events. Limitation: Low compliance at 56%, and high attrition within the groups: creatine (n=86 of n=120) and placebo (n=88 of n=117) , 61% compliance for exercise sessions completed.

Clinical practice applications

Creatine supplementation is effective for increasing lean tissue mass when combined with resistance training that may allow for increased mechanical stress on bone, stimulating a net bone formation.

Considerations for future research

Assess the mechanism of action of creatine supplementation on BMD.
Longer term follow-up with larger sample sizes would be needed to confirm protection against hip fracture with creatine supplementation.

Abstract

PURPOSE

Our purpose was to examine the effects of 2 yr of creatine monohydrate supplementation and exercise on bone health in postmenopausal women.

METHODS

Two hundred and thirty-seven postmenopausal women (mean age, 59 yr) were randomized to receive creatine (0.14 g·kg -1 ·d -1 ) or placebo during a resistance training (3 d·wk -1 ) and walking (6 d·wk -1 ) program for 2 yr. Our primary outcome was the femoral neck bone mineral density (BMD), with lumbar spine BMD and proximal femur geometric properties as the secondary outcomes.

RESULTS

Compared with placebo, creatine supplementation had no effect on BMD of the femoral neck (creatine: 0.725 ± 0.110 to 0.712 ± 0.100 g·cm -2 ; placebo: 0.721 ± 0.102 to 0.706 ± 0.097 g·cm -2 ), total hip (creatine: 0.879 ± 0.118 to 0.872 ± 0.114 g·cm -2 ; placebo: 0.881 ± 0.111 to 0.873 ± 0.109 g·cm -2 ), or lumbar spine (creatine: 0.932 ± 0.133 to 0.925 ± 0.131 g·cm -2 ; placebo: 0.923 ± 0.145 to 0.915 ± 0.143 g·cm -2 ). Creatine significantly maintained section modulus (1.35 ± 0.29 to 1.34 ± 0.26 vs 1.34 ± 0.25 to 1.28 ± 0.23 cm 3 (placebo), P = 0.0011), predictive of bone bending strength, and buckling ratio (10.8 ± 2.6 to 11.1 ± 2.2 vs 11.0 ± 2.6 to 11.6 ± 2.7 (placebo), P = 0.011), predictive of reduced cortical bending under compressive loads, at the narrow part of the femoral neck. Creatine reduced walking time over 80 m (48.6 ± 5.6 to 47.1 ± 5.4 vs 48.3 ± 4.5 to 48.2 ± 4.9 s (placebo), P = 0.0008) but had no effect on muscular strength (i.e., one-repetition maximum) during bench press (32.1 ± 12.7 to 42.6 ± 14.1 vs 30.6 ± 10.9 to 41.4 ± 14 kg (placebo)) and hack squat (57.6 ± 21.6 to 84.4 ± 28.1 vs 56.6 ± 24.0 to 82.7 ± 25.0 kg (placebo)). In the subanalysis of valid completers, creatine increased lean tissue mass compared with placebo (40.8 ± 5.7 to 43.1 ± 5.9 vs 40.4 ± 5.3 to 42.0 ± 5.2 kg (placebo), P = 0.046).

CONCLUSIONS

Two years of creatine supplementation and exercise in postmenopausal women had no effect on BMD; yet, it improved some bone geometric properties at the proximal femur.