The study failed to produce a change in the primary outcome measure - sit to stand test - but did find a marked improvement in the walking speed and balance tests of the intervention group.
Good physical performance is central to active and healthy aging. Physical performance relates not only to the musculoskeletal system, but also to other aspects of daily living.
Sarcopenia can be defined as low muscle strength, mass, and quality which increases with aging. Loss of muscle mass is associated with malnutrition, low protein intake, low physical activity, inflammation, chronic disease, unintentional weight loss, and low body mass index.
Milk fat globule membrane (MFGM) is composed primarily of lipids and proteins that surround fat globules in mammal milk. It is a source of multiple bioactive compounds, including phospholipids, glycolipids, and glycoproteins, that have important functional roles within the brain and gut.
Hydrolysed milk protein is absorbed more rapidly than intact protein and increases postprandial amino acid availability; thus, it may augment postprandial muscle protein synthetic response in older people.
Therefore, researchers from the University of Helsinki, in Finland, conducted this study in which they supplemented older women with protein intake below the recommended level with a drink high in MFGM and hydrolysed protein, to test whether this improved their physical performance.
They found the intervention did not lead to a significant difference in five-time-sit-to-stand test in the intervention group compared to the control group in older women. However, the balance test score of the SPPB changed significantly, as did the SPPB total score, mainly due to the balance and walking speed scores, favouring the intervention group. In fact, the effect size (ES) for the difference between changes in groups (ES 0.42) was quite good, indicating significant improvement.
Research background
Previous studies on physical function and performance have found that MFGM supplementation may stimulate neuromuscular junction development, which is a critical structure of motor units involved in physical movement. Therefore, the authors of this study propose its possible that an increase in cognitive motor units may lead to improvement in physical function and performance.
Interventions including MFGM supplements combined with exercise have improved ambulatory activities, leg muscle mass, and muscle fiber velocity in older adults. One study found MFGM supplementation given to middle-aged adults as part of a regular exercise regime enhanced physical agility by promoting fast-type motor unit maintenance compared to a control group.
However, so far, most of the research on MFGM supplementation on physical performance has been published from Japan, with no data on the effects of MFGM supplementation on other ethnic groups.
The study
In 2021, 101 older, home-dwelling women (≥70 years) were recruited to the study and sarcopenia was screened with the SARC-F questionnaire.
The participants were randomly assigned to the intervention or control group. The intervention group received a daily drink product containing MFGM and protein for 12 weeks. In addition, both groups (intervention and control) were taught and advised on a simple five-movement exercise routine, which they were encouraged to independently perform every day during the study. To monitor their compliance with the advice, the participants filled out a daily track sheet, where they reported whether they had consumed a snack product and/or performed the exercise.
Participants in the intervention group were offered either a protein powder or milkshake. The serving size of both products contained the same amount of protein (23 g) and a similar amount of MFGM (powder 3.9 g and milkshake 3.6 g).
The participants were followed up for 12 weeks. The primary outcome of the study was the difference in changes in the five-time-sit-to-stand test between the intervention and the control groups. The five-time-sit-to-stand test was measured during baseline and end visits at 12 weeks as part of the Short Physical Performance Battery (SPPB) test, which additionally includes walking speed, balance tests, and grip strength.
Cognition was measured using Trail Making Test (TMT), which test attention and psychomotor speed and good executive function (Reitan 1958). Health-related quality of life was assessed using the RAND-36 test, which is validated in the Finnish population.
Energy and protein intakes were measured using a 3-day food diary before the baseline visit to verify whether potential participants met the inclusion criteria on protein intake (protein intake < 1.2 g/kg body weight (BW)/d). In addition, 3-day food diaries were collected at the end of the trial to see whether the use of snack products increased the protein intake and energy intake of the participants.
Results
A total of 94 participants completed the trial. The main outcome of the study, the change in the five-time-sit-to-stand test, did not differ between the intervention and control groups - both groups somewhat improved.
However, the change in total SPPB score differed significantly (+0.8 points in the intervention group vs. 0.2 points in the control group). The improvement in the intervention group derived mainly from the improved balance test in the intervention compared with the control.
The researchers note that the study has several limitations, most notably the failure to produce a change in the primary outcome.
The report states: "Since our study was designed based on the primary outcome including sample size, the interpretation of secondary outcomes and generalization of the results should be cautiously considered, because the failure of the primary outcome may significantly affect the statistical power of secondary outcomes."
But they say the results provide good guidance for future research: "In the future, balance and fall prevention could be considered as primary outcomes in studies with MFGM or MFGM combined with protein, especially in study designs without mandatory exercise. It would also be interesting to see the results of RCTs on diverse groups of older people to learn who would possibly benefit the most from these types of interventions."
Source: Nutrients
https://doi.org/10.3390/nu15132922
"Effect of Milk Fat Globule Membrane- and Protein-Containing Snack Product on Physical Performance of Older Women—A Randomized Controlled Trial"
Authors: yväkorpi, S.K.; Niskanen, R.T.; Markkanen, M.; Salminen, K.; Sibakov, T.; Lehtonen, K.-M.; Kunvik, S.; Pitkala, K.H.; Turpeinen, A.M.; Suominen, M.H.