Study under review: Collagen peptide supplementation in combination with resistance training improves body composition and increases muscle strength in elderly sarcopenic men: a randomised controlled trial
The term “sarcopenia” refers to the age-related loss of muscle mass, which can lead to a reduction in functional muscular performance and possibly physical disability. Sarcopenia can develop from a variety of factors, including neurological and hormonal changes, chronic inflammation, reduced physical activity, and poor nutrition. It is associated with a number of short and long-term negative health outcomes, including increased insulin resistance, fatigue, frailty, falls, and all-cause mortality.
Sarcopenia is classified according to its progression, which is quantified based on the amount of skeletal muscle a person has compared to the sex-specific average for young adults (aged 18-39). This is expressed as the skeletal muscle mass index (SMI = skeletal muscle mass / body mass x 100). Depending on the amount of muscle mass a person has, sarcopenia is considered either class I or class II (the prevalences of each are shown in Figure 1). Class I sarcopenia is present when someone’s SMI is within one to two standard deviations below young adult values, while class II sarcopenia is diagnosed when SMI is more than two standard deviations below young adult values.
It should come as no surprise that resistance training can delay and slow down this age-associated decrease in muscle mass and function. It has also been established that supplemental dietary protein can increase the rate of muscle protein synthesis and decrease muscle protein breakdown after exercise. A 2012 meta-analysis of 22 trials concluded that “protein supplementation increases muscle mass and strength gains during prolonged resistance-type exercise training in both younger and older subjects.”
It’s generally thought that protein consumed after resistance training should be rich in the branched chain amino acid (BCAA) leucine, due to its potential to activate the anabolic mTOR pathway. Whey protein is naturally high in leucine, which is in part why it has become a post-workout staple for muscle building. In contrast, collagen is considered to be of lower biological value due to its low content of the BCAAs leucine, isoleucine, and valine, as well as its total lack of cysteine and the essential amino acid precursor methionine. With that in mind, it may be surprising that at least one study has suggested collagen may in fact be better than whey for maintaining overall nitrogen balance (a way of measuring protein metabolism) during a low-protein diet. This may be due to the type of amino acids prevalent in collagen containing more than one nitrogen atom and/or having a low molecular weight.
Since the effects of collagen protein as a post-workout supplement in older adults with sarcopenia had yet to be studied, this group of German researchers examined the effects of post-workout supplementation with hydrolyzed collagen on muscle mass and muscle function in elderly men with sarcopenia during a three-month resistance training program.
Sarcopenia, the age-associated loss of muscle mass that can lead to functional impairments and disability, has been linked to metabolic disease and is associated with increased risk of all-cause mortality. This is a significant health issue that can be improved through resistance training and/or dietary protein consumption.
Other Articles in Issue #12 (October 2015)
Eat less, live more
Animal trials suggest that calorie restriction may extend lifespan. This is the longest human trial conducted thus far on the topic, and serves to inform calorie restriction’s health impacts and feasability.
Am I less hungry after I eats me spinach?
The gut is a hot weight loss topic, even aside from the microbiome -- some pharmaceutical drugs attempt to manipulate hormones or fat digestion in order to spur weight loss. What if an extract of spinach could also impact these factors?
Sugar Wars, Episode 2: “Fructose Strikes Back”
Few food components have been demonized as much as fructose in the past decade. With fructose being presumed guilty in metabolic syndrome and heart disease, this systematic review sheds light on it’s actual impact on blood lipids.
The case of the misleading yohimbe labels
What’s actually in a supplement bottle can be a mystery. These intrepid researchers investigated the actual contents of yohimbe bottles in order to see if this popular but possibly sometimes quasi-legal supplement is more (or less) than meets the eye.
- Interview: Robert Krikorian Ph.D.
Paying attention to omega-3s for ADHD
With more and more people being diagnosed with ADHD, there’s a continuing hunt for helpful treatments. Researchers tested an omega-3 supplement on young males, and also explored a potential dopamine-related mechanism.
- Interview: Trevor Kashey, Ph.D.
Throwdown, round 1: plant vs animal protein for metabolic syndrome
The DASH diet is frequently tested in clinical trials, and often performs well. But the diet’s formulation includes strong limitations on red meat, which may be based on outdated evidence. This study compared animal-protein rich diets with a typical DASH diet.
Can omega-3s modulate the mind-muscle connection?
While strength gains are usually associated with protein and muscle-related ergogenics, the nervous system isn’t targeted as often. This study explored a different type of omega-3 source (seal oil) for neuromuscular exercise effects.