運動＋蛋白質摂取によるGFR変化

地域在住高齢者における12週間のレジスタンス運動＋運動後のたんぱく質摂取によるGFR（糸球体濾過量）の変化を見た論文を紹介します。

Ramel A, Arnarson A, Geirsdottir OG, Jonsson PV, Thorsdottir I. Glomerular filtration rate after a 12-wk resistance exercise program with post-exercise protein ingestion in community dwelling elderly. Nutrition. 2013 May;29(5):719-23. doi: 10.1016/j.nut.2012.10.002.

レジスタンス運動は12週間、週3回実施しています。たんぱく質はホエイたんぱくもしくは牛乳たんぱくを1日20g摂取、運動後に摂取しています。GFRの平均値は70.7 ± 16.9で、25.4%が60未満でした。

結果ですが、 レジスタンス運動＋たんぱく質20gの摂取によって、GFRは有意に改善しました（介入後平均75.1 ± 20.2）。また、GFR60未満の群でも介入で有意に改善しました（介入前：48.9 ± 10.3、介入後53.4 ± 12.9）。

以上より、地域在住高齢者における12週間のレジスタンス運動＋運動後のたんぱく質20gの摂取は、GFRに悪影響を与えないという結論です。

CKDではたんぱく質摂取を制限することが推奨されがちです。しかし、GFR60未満の群（Stage3）では、12週間の運動＋たんぱく質投与によるGFR悪化は認めず、むしろ改善しました。CKDStage3では運動＋たんぱく質投与をむしろ行うべきかもしれません。

Abstract

OBJECTIVE:

Increased protein intake and resistance exercise can be beneficial for maintenance of lean body mass (LBM) in older adults. However, these factors could also negatively affect renal function. We investigated changes in renal function after a 12-wk resistance exercise program combined with protein supplementation in community dwelling older adults.

METHODS:

Patients (N = 237, 73.7 ± 5.7 y, 58.2% female) participated in a 12-wk resistance exercise program (3 times/wk) designed to increase strength and muscle mass of major muscle groups. Participants were randomly assigned to one of three dietary supplements consumed directly after training: whey protein drink (20 g whey protein, 20 g carbohydrates), milk protein drink (20 g milk protein, 20 g carbohydrates), or carbohydrate drink (40 g carbohydrates). Renal function was estimated as glomerular filtration rate (GFR, Cockcroft-Gault formula), and dietary intake was measured as 3-d-weighed food record at baseline and endpoint.

RESULTS:

During the intervention, energy intake did not increase. Carbohydrate intake increased in the carbohydrate group and protein intake increased in the milk group, both approximately in accordance with the supplementation. In the whey group, protein intake did not increase, but carbohydrate intake did. GFR increased after the intervention (+4.4 mL/min/1.73 m2; P < 0.001), and the changes were similar in men and women or in the age quartiles. Changes in GFR at endpoint were not associated with LBM, dietary supplements, or total protein intake.

CONCLUSIONS:

A 12-wk resistance exercise program combined with protein supplementation in community dwelling older adults does not negatively affect GFR. The supplementation had only minor effects on total dietary intake.