More Evidence That Muscle Saves Lives

[00:03:00]   Motivating factors contributing to doing this study.

• The associations between muscle and aging and the way we often measure it in studies, is not as strong as you would expect.
• Muscle quality is important, but it seems that the absolute amount of muscle mass a person has, is indispensable.
• DEXA scans have limitations.
• Another tool was needed to accurately measure muscle mass.
• The D3-Cr (Deuterated Creatine Dilution) protocol to assess muscle mass, was intriguing.

[00:05:21]   D3Cr uses a labeled Creatine, explain what that does?

• We leverage some facts about creatine biology to make this work.
  • Almost all the creatine in your body is found in the muscles.
  • Figuring out how much creatine is in your body will enable you to figure out how much muscle you have.
  • Creatine is found in the muscle at a relatively constant concentration.
  • Creatine is converted to creatinine which is rapidly excreted in the urine.

[00:09:32]   This measurement focusses on measuring the energetic potential of muscles as opposed to the total amount of muscle.

[00:11:37]  The design of the study:

• This study was 1 of many in a Project.
• 1 Of the studies was called, The osteoporotic fractures in men study.
  • Was initially designed to look at risk factors for fracture in older men.
  • The study expanded its focus from just osteoporosis to other conditions of aging.
  • The muscle mass measure was added to one of the follow-up visits.
  • The D3Cr is strangely predictive of mortality.
  • People with below 25% of the muscle measures, we are 3 times more likely to die than people in the highest quartile.
  • People in that lowest 25% were about 6 times more likely to have a hip fracture than people in the upper quartile.

[00:14:14]   Bone mineral density is affected tremendously by how strong you are. The stronger you get, the greater, the demand for mineralization of your bones becomes.

[00:16:56]   Carl talks about the California VA Study.

[00:17:36]   Dr Peggy elaborates on the mortality factor in her study.

[00:19:43]   The number one risk factor for Dementia and Alzheimer's is metabolic derangement.

[00:21:03]   For scientists understanding the way exercise works will help uncover pathways that we could have other therapies to improve mobility for very frail or injured people.

[00:21:40]   Carl eloquently discusses about anabolic steroids and SARMs (selective androgen receptor modulators), you have to listen!

[00:25:56]   Were there any things that jumped out at you in this research?

• It was surprising to me is how close to what we expected the results were when they were even a little bit stronger than I expected.
• The association with hip fracture results was a major surprise
• The fact that the measure of muscle mass is a strong predictive of mortality was also surprising.

[00:27:58]   What do you hope people take away from your research?

• That it reinforces that muscle saves lives.
• That muscle's importance is often overlooked.
• To get clinicians in particular to think about muscle and how to implement assessing muscle either through this measure or through a standardized measure for muscle function.
• To produce a standard way to measure and integrate it into clinical care.

[00:29:00]   Carl suggests the bodybuilding way of measuring muscle mass, Dr Peggy replies.

[00:31:56]   Is muscle mass independently important of the strength that the muscle produces?

• The data shows that it is both mass and how strong you are that are associated with things like disability, immobility, and hip fractures.

[00:33:00]   An interesting discussion ensues on  the possibility of a formula that intersects muscle mass and its ability to function.

[00:36:38]   Carl shares his theory on metabolic debris accumulation, tissue innervation and blood flow  – tune in!

[00:37:14]   Dr Peggy replies on Carl’s theory that there is a new study where muscle biopsies were done on about 900 older people. Results will be out soon.

[00:41:12]   Limitations and next steps for the project.

• The big limitation of our study is that this measure was added to an ongoing study of older men that were mostly white.
• We therefore do not have a lot of data about particularly important subsets of the population like women or minority populations or people outside the U S.
• We have been doing a lot of work to add this measure to certain studies that have this measure in women or to under-representative populations.
• The associations are mostly the same in women, but there may be a few significant differences.
• We would like to understand all the differences.

[00:42:03]   As a rule, women live longer, but with more disability. The aim is to figure out what role muscle plays in this fact.

[00:43:04]   The noble pursuit of muscle – stronger is younger!