肥満女性の減量・運動とサルコペニア

閉経後の過栄養～肥満女性に対する食事、運動、ビタミンDがサルコペニアに与える影響を調査した論文を紹介します。

Mason C, Xiao L, Imayama I, Duggan CR, Foster-Schubert KE, Kong A, Campbell KL, Wang CY, Villasenor A, Neuhouser ML, Alfano CM, Blackburn GL, McTiernan A. Influence of Diet, Exercise, and Serum Vitamin D on Sarcopenia in Postmenopausal Women. Med Sci Sports Exerc. 2012 Nov 27. [Epub ahead of print]

対象は439人の閉経後の過栄養～肥満女性で、12ヶ月間、食事療法群、運動療法群、食事＋運動群、対照群の4群に分けられました。食事療法は10％の体重減少を目標としました。運動療法は1日45分、週5回の中強度の有酸素運動です。

結果ですが、食事療法群では筋肉量が対照群より有意に低下しました。運動療法群では筋肉量が保たれていました。食事＋運動群では筋肉量減少を認めましたが、食事療法群よりその程度は軽く、対照群と比べて有意差はありませんでした。

以上より、減量時の有酸素運動は筋肉量減少を緩和し、サルコペニア予防となる可能性があるという結論です。

サルコペニア予防には有酸素運動よりレジスタンストレーニングのほうが効果を期待できますが、有酸素運動でも一定の効果はあるようです。食事療法だけで減量すると筋肉が減って、その後リバウンドすると脂肪で増えるので、サルコペニア肥満に一直線ですね。

Abstract

PURPOSE:

To investigate the effects of 12 months of dietary weight loss and/or aerobic exercise on lean mass and the measurements defining sarcopenia in postmenopausal women, and to examine the potential moderating effect of serum 25-hydroxyvitamin D (25(OH)D) and age.

METHODS:

439 overweight and obese postmenopausal women were randomized to: diet modification (N=118); exercise (N=117), diet+exercise (N=117), or control (N=87). The diet intervention was a group-based program with a 10% weight loss goal. The exercise intervention was 45 mins/day, 5 days/week of moderate-to-vigorous intensity aerobic activity. Total and appendicular lean mass were quantified by dual Xray absorptiometry (DXA) at baseline and 12 months. A skeletal muscle index (SMI=appendicular lean mass (kg)/m) and the prevalence of sarcopenia (SMI<5 .67=".67" calculated.="calculated." class="highlight" kg="kg" m="m" span="span" were="were">Serum
25(OH)D was assayed using a competitive chemiluminescent immunoassay.

RESULTS:

Dietary weight loss resulted in a significant decrease in lean mass, and a borderline significant decrease in appendicular lean mass and SMI compared to controls. In contrast, aerobic exercise significantly preserved appendicular lean mass and SMI. Diet + exercise attenuated the loss of appendicular lean mass and SMI compared to diet alone, and did not result in significant loss of total- or appendicular lean mass compared to controls. Neither serum 25(OH)D nor age were significant moderators of the intervention effects.

CONCLUSIONS:

Aerobic exercise added to dietary weight loss can attenuate the loss of appendicular lean mass during weight loss, and may be effective for the prevention and treatment of sarcopenia among overweight and obese postmenopausal women.