Sunday, May 1, 2011

Its Never Too Late for A Good Steak: Resistance Exercise + 340g Lean Beef Double Muscle Fractional Synthesis Rate in Young and Old

While this is not part of the statistic, my Blogger account provides, I assume that most of you, the students of the SuppVersity, are way below the golden ages of 60+. Yet, even if this is the case, everyone will have a parent, a grand parent, friends or acquaintances, who have a few more years under their belts and begin to complain about little aches and pains. Now, you have good news for these people: They may well avoid many of these maladies by maintaining or even building new muscle mass, if they just follow the same simple principles, of which I hope you already adopted them. Work out & eat healthy with a focus on high quality protein sources to boost protein synthesis and stop protein breakdown.
Figure 1: It's beyond me, why one would even question the value of a mouth-watering piece of beef?
(photograph by Michael C. Berch (User:MCB) on 2006-11-25, Wikipedia)

A very recent study from the University of Texas (Paddon-Jones. 2011), where a "quality protein source" is of course a peace of premium quality Texan lean  beef (340g), confirms that these principles, i.e. working out and fueling the protein anabolic effects with adequate amounts of protein, apply equally to younger (n=7, 29±3 y) and older (n=7, 67±2 y) subjects:
Fixed muscle fractional synthesis rate (FSR) was calculated during a 3 h post-absorptive/rest period and again during a 5 h period following ingestion of a protein-rich meal (340 g lean beef) and bout of resistance exercise (6 sets of 8 repetitions of isotonic knee extension exercise at 80% one repetition maximum). [...] Mixed muscle FSR increased by approximately 108% in both young [pre: 0.073±0.008; post: 0.156±0.021(SE) %/h, p<0.001] and older adults (pre: 0.075±0.004; post: 0.152±0.017 %/h, p=0.003) following the meal and resistance exercise bout. 
In that, it is certainly no coincidence that lean beef contains almost as much leucine (8% leucine, 4% valine, 4% isoleucine) as whey, which - due to this its high leucine intake - has been shown to optimize protein synthesis via mTOR- and AKT pathways in various studies, about many of which you will probably have read on the SuppVersity, anyways.
Figure1: Comparison of amino acid profiles of 90% lean ground beef vs. Whey powder
(data adapted from
A direct comparison of whey vs. lean beef on a gram per gram basis (cf. figure 1) is nevertheless deceiving, because the time it takes for your digestive system to "dissolve" the meat (it will be different for processed beef protein powder, though), so that the proteins can be broken down and the amino acids may "do their magic". It was thus only consequent of the researchers to a) use a much larger amount of beef (340g vs. 30g whey in many studies) and to b) extend their experiment to 5 hours, which should be about the amount of time, it will take to fully digest the 340g of lean beef with it's whopping 28g of leucine.

Bottom line: If your daddy refuses to sip on a sweet chocolate whey, because he doesn't "do steroids", serve him some (preferably grass fed) beef before you drag him to the gym ;-)