Welcome to Straight Talk on Health. I’m your host Dr. Chet Zelasko. Straight Talk on Health is a joint production with WGVU in Grand Rapids MI. I examine the practical application of health information. Nutrition. Exercise. Diet. Supplementation. I look at the science behind them, and let you know whether it’s something to consider or not. You can check out other things that I do on my website Drchet.com and sign up for my free emails.
I thought I would focus on exercise physiology in this episode. The first is about the supplement creatine. It got some press because of a recent study that suggested it doesn’t build muscle. The second was about the physiology of a 92-year-old world champion rower. Just an incredible research paper. But let’s start with creatine.
What exactly is creatine? Creatine is a naturally occurring chemical your body makes by combining glycine, arginine, and methionine. It’s primarily used in energy production as a precursor in the manufacture of ATP in your body. In fact, it’s your immediate energy supply. Creatine binds with a phosphate molecule and can readily give up the phosphate group to ADP to make ATP. The problem is that you only have about a 7-30 second supply at maximal effort—and I mean maximal—in your muscles. Fortunately, your body shifts into other forms of energy production so you don’t run out of the ability to make more energy.
Creatine is often used to help increase muscle mass in people who train with weights and that’s the focus of the paper I’m going to review.
Researchers in Australia recruited male and female subjects who had been sedentary and had not done any form of resistance training or creatine supplementation in the past year. They collected data on 33 controls and 30 experimental subjects for a 13-week creatine supplementation and resistance training study. The objective was see if there were actual changes in muscle mass and lean body mass within the RT and supplementation program. Prior research had shown that creatine may only change water levels as creatine does increase fluid levels in muscle.
The tool they used to assess fluid levels was DEXA to scan for LBM before the study began, after the 7-day wash in period with creatine, and after the 13-week RT program. What they found was that LBM increased during the wash in period in the supplementation group before the RT program began. The difference in LBM was maintained throughout the RT program. In response to the RT program, both groups increased LBM by 4.4 pounds after accounting for the initial difference in BW. Therefore, they concluded that creatine may not contribute to increases in LBM when used in a RT program because of the lack of difference between the supplement and the placebo group once the initial LBM was accounted for.
Or maybe it really does. To their credit, they pointed out that the small difference in fluid levels were within the standard error of the measurement method. Still, they maintained that because the difference was maintained throughout the RT part of the study, the benefit of creatine to muscle gain should be assessed with higher doses. I’m all for more research but they made some errors in logic and variables they tested.
The initial error was in their subject group. Using both men and women was a good idea as too many studies are done without female subjects. The problem was using such a diverse age group at 18 – 50 years old. Research has shown that muscle loss due to age can begin as early as 40 – 50 years of age. Because they had so few subjects at 63, that means that ideally it would mean 15 men and women in each group. Dividing those few subjects into under 40 and over 40 means as few as 6-7 subjects in each group. That’s just not enough subjects to prove their point.
They also forgot one of the basic tenets of muscle physiology: the force a muscle can generate is directly proportional to its cross-sectional area. The fact that creatine increases the cross-sectional area of the muscle, albeit temporarily, might allow the people using creatine to lift heavier weights throughout the study. This was only a 12-week training program in non-exercisers. A better approach might have been to use currently lifting subjects who were not using any type of dietary supplement. It could take a lot longer, maybe years, for the muscle mass to separate due to creatine from users to non-users. And then throw in the age factor and there really is a lot of research to be done.
But one thing may have been able to shed some light on this: where was the strength data? Looking at LBM is looking at a combination of factors, but strength is strength: how much weight can you lift in several lifts like the dead lift, the squat, and the bench press. You can’t do such an intensive study and not measure the simplest variable. It’s a rookie mistake. I know because I did it. When I turned in my dissertation for review, I didn’t put in the exercise data—the change in fitness levels. The discussion was short and I quickly saw the merit of putting the data into my dissertation. I had it but chose not to put it in. In a study that includes exercise.
Creatine is a natural substance that may be beneficial for a variety of things besides muscle growth. I use it every day because I also lift to increase strength but because it benefits the skin, muscles, and other organs as well. I don’t think this study is definitive and unless you can’t take it, I think everyone over 40 probably should.
Let’s turn to a study, really a case report, published in the Journal of Applied Physiology. Researchers wanted to get a profile of a 92-year-old champion rower. Before I get into the fitness details, the story behind the man goes something like this. He was a baker for most of his life. He began rowing at 73 yr of age and before that, did not have any structured training or exercise training. He was a lightweight (under 165 pounds) 2,000-m master indoor rower and four-time world champion having in 2007, 2017, 2021, and 2022). His diet was healthy and he had developed a consistent training program: 30 km/wk or about 18 miles, which was 40 min/day on the rowing ergometer. He supplemented the aerobic work with 2–3 days/wk of resistance training specific to rowing.
What his fitness like, especially compared to men of other ages? He was 5’4” tall and 165 pounds. That’s just about right in his weight for height. When it comes to lung and heart function, while they seemed a little low at a sustained competitive O2 capacity of 21 ml/kg/mi, there are really no comparative data with other 90-year-old athletes. Relatively speaking, the authors speculated that he had a fitness level of a 40-year-old. What they didn’t really say was that the 40-year-old was in the average fitness category.
But listen up. That doesn’t take anything away from the amazing fitness level of a 92-year-old man. It should mean a couple of things to us:
First, it’s never too late to begin a fitness program. True, this was unifocal in purpose, using an indoor rowing machine, but it doesn’t change his remarkable fitness level.
Second, he was consistent in his training once he began. He consistently exercised for over 20 years, building on what he’d done before but not going crazy nuts with his training. In other words, he didn’t do it to extremes. He just plodded along. That’s a fine lesson for everyone, regardless of age but especially those over 70. Amazing!
That’s it for this episode. If you like this podcast, please hit the like button and tell your friends and colleagues about it. Until next time, this is Dr. Chet Zelasko saying health is a choice. Choose wisely today and every day.
Reference: Journal of Applied Physiology
Volume 135, Issue 6 December 2023 Pages 1415-1420
Nutrients 2025, 17, 1081
