Effects of low-dose milk protein supplementation following low-to-moderate intensity exercise training on muscle mass in healthy older adults: a randomized placebo-controlled trial

Abstract

Purpose The purpose of this study was to examine whether long-term ingestion of low-dose milk protein supplementation causes a greater increase in muscle mass and strength of older adults during low-to-moderate intensity exercise training intervention than isocaloric carbohydrate. Methods In a randomized, double-blind, and placebo-controlled design, 122 healthy older adults (60–84 year) received either an acidified milk protein drink containing 10 g of milk protein (MILK; n = 61) or an isocaloric placebo drink (PLA; n = 61) daily throughout 6 months of body weight and medicine ball exercise training. Measurements before and after the intervention included body composition, physical performance and blood biochemistry. Results Lean body mass significantly increased in the MILK group (+ 0.54 kg, p < 0.001), but did not change in the PLA group (− 0.10 kg, p = 0.534). The increases in the MILK group were significantly greater than in the PLA group (p = 0.004). Fat mass (− 0.77 kg) and plasma uric acid levels (− 0.3 mg/dL) significantly decreased only in the MILK group (p < 0.001), with a significant group difference (p = 0.002 and p < 0.001, respectively). Most of the physical performance tests significantly improved in both groups, but no group differences were found. Conclusion We conclude that low-dose milk protein supplementation (10 g of protein/day) combined with low-to-moderate intensity exercise training is associated with increased muscle mass, but not improved physical performance compared to carbohydrate combined with exercise in healthy older adults. This study was registered in the UMIN Clinical Trials Registry (UMIN000032189).

Systematic review and meta‐analysis of protein intake to support muscle mass and function in healthy adults

“…However, it is relevant to highlight that the study of Nakayama et al ., 76 was the main contributor to this result according to our sensitivity analysis. Probably, because the study sample in Nakayama et al 76 . is relatively large ( n = 122) when compared with other studies in the subgroup analysis.…”

“…Sixty‐six out of 74 studies were included in the lean body mass change analysis, utilizing 2665 subjects 33–99 . Six studies presented intervention groups not using RE training 41,46,94,97–99 ; of these, four studies tested protein ingestion exclusively, 41,97–99 and two studies tested protein ingestion in groups without and with resistance exercise 46,94 .…”

“…Six studies presented intervention groups not using RE training 41,46,94,97–99 ; of these, four studies tested protein ingestion exclusively, 41,97–99 and two studies tested protein ingestion in groups without and with resistance exercise 46,94 . Changes in strength data resulting from the additional protein intervention were extracted from 50 studies testing 2283 subjects for lower‐body strength 33,36–39,43,44,47–49,52–58,61–65,67–70,72,74–78,82,84,86,88–92,94,96,100–104 and only three studies with intervention groups without RE 41,99,105 . Thirty‐four studies tested bench‐press strength 33,36–38,43,47–49,53–55,62–65,67,68,70,72,74,75,77,78,82,84,86–88,90,91,93,95,96,99 with 1049 subjects.…”

Dietary Protein Requirement Threshold and Micronutrients Profile in Healthy Older Women Based on Relative Skeletal Muscle Mass

“…In the present study, we observed the consumptions of higher amounts of protein, iodine, polyunsaturated fatty acids (PUFA), Vit E and manganese are favourable for maintenance of muscle level above the pre-sarcopenic threshold using SMM r . It is possible that food types may underlie the lower nutrient intake, where the high SMM r group had a diet richer in fish, milk, nuts and seeds, considered a high diet quality [ 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 ]. The association of higher dietary intake of protein with better muscle phenotypes in the present study could be explained by the reported positive link between dietary protein intake and muscle protein synthesis [ 6 ].…”

Does the Combination of Resistance Training and A Nutritional Intervention Have A Synergic Effect on Muscle Mass, Strength, and Physical Function in Older Adults? A Systematic Review and Meta-Analysis

“…Among the included studies, two studies provided an appropriate amount of protein (10 g milk protein and 0.5 g/kg whey protein) three times a day, taking into account frequency and distribution [21,25,26]. Other studies provided 10.1 g-25 g protein once a day [44][45][46][47] or 20 g ~ 35 g protein 3 times a week on the days exercise was performed [48][49][50]. A previous review showed that multi-ingredient protein supplements have the potential to increase the bene ts of resistance training, but there were no differences in the effects on muscle mass and strength between multi-ingredient protein and single protein [51].…”