Transcription
Hello, this is Dr. Ford Brewer, PrevMed. Heart attack, stroke, cancer prevention, disability prevention—prevention sometimes takes some discipline in terms of lifestyle, but it's a heck of a lot better than getting a bypass graft or becoming senile.
This is an image of what happens with the aging process and the impact of decreased mitochondrial function on aging. That's called the mitochondrial theory. Why are we talking about that again today? This may sound like science, but actually, we're talking about a very practical thing: high-intensity intervals (HIIT), high-intensity interval training. We're discussing this not just for young people, but for older people as well—65 to 80-year-olds. We're going to talk about a study where there were two groups: 18 to 30 and 65 to 80. They put them through several months of interval training and looked at heart, lung, and circulation performance, as well as mitochondrial performance.
So, let's go back and talk about the mitochondria again. This is an image of the mitochondrial process of aging. The first step is damage to the DNA in the nucleus. If you look at Valter Longo and the mimicked fasting activities, his point would be that it's not even that the DNA is damaged; it's just that it's not being transcribed. I think David Sinclair would talk about the lack of transcription of some controlling genes as well.
If you look at this second stage, the first stage is DNA—whether it's DNA damage or lack of transcription driven by some controlling genes—they still start hitting a lot of the same pathways. The pathways used in respiration, and the center of respiration is the mitochondria. Again, you'll see some names that we mentioned in other videos: C1 or the SIRT1 gene, being researched by David Sinclair at Harvard. AMPK—these are impacted by metformin and again help the cell take food and turn it into energy. So, if these metabolic pathways are damaged, then basically you're getting damage in the performance of the mitochondria, and the mitochondria are the powerhouse of the cell.
This last image shows that damaged mitochondria lead to neurodegenerative damage, in other words, senility. You get damage to the heart and lungs, basically aging tissue. So, the human goes from peak health in adulthood to poorer health as an older individual.
Who did this research? His name is Shamarian Nir. Where is he? He's a faculty member at the Mayo Clinic in Rochester. He is a cellular biologist who has been doing a lot of work on cellular metabolism, aging, and mitochondria—again, all of these areas that we've just been talking about.
What did he do? As I said, he took two groups of people: one group was 18 to 30 years old, and the other group was 65 to 80 years old. He had them doing high-intensity interval training for, I believe, it was three months. He looked at the performance of the heart and lungs, and he actually did biopsies of the muscles to look at the mitochondria. This is an unusual study in that he actually did muscle biopsies; you don't see a lot of studies where they've done that. What that does is create a lot of value for the study because now we can start looking at the cells, looking on an intracellular level at the mitochondria to see what the impact was.
Here's what he saw: on the youngsters (18 to 30), there was a 28% improvement in heart, lung, and circulation health parameters. In the older folks (65 to 80), there was a 177% improvement. What about the muscle biopsies in mitochondrial function? There was a 69% improvement in mitochondrial function in the older folks and a 49% improvement in the young group. The younger group had mitochondria that were already healthier to start with and didn't have quite as much improvement they could experience, which is exactly what you'd expect.
Now, when you see some reviews of the study, one of the reviews said, "Look, it didn't make them younger." In fact, if you did high-intensity intervals but were eating donuts all day long, you're still going to be in bad shape. I get it; I think we all understand that. But again, this was a great study in that it actually showed improvement of mitochondrial function using muscle biopsies.
Now, a lot of my patients are 65 to 80 years old, and they're folks that are basically just doing one or two miles of walking three or four times a week for their exercise. How can they get high-intensity intervals? They can walk up hills, carry a weight vest, use a bicycle ergometer, or an elliptical trainer.
How do you measure it? You can measure it with pulse; you can measure it with increased breathing. What's the impact of high-intensity intervals on insulin resistance? It is the number one exercise that improves insulin resistance, which is the number one cause of cardiovascular inflammation. Again, maybe it's because of this improvement in mitochondrial function.
So, what about interval training for younger people? Again, you can use similar methods. You can do it with running. Professional cyclists have a very simple type of high-intensity interval training; many of them use a 45-second high-intensity interval with a 30-second recovery phase. So, again, two phases to an interval: the high-intensity phase where you're going—this needs to be high-intensity, with a pulse well over 100. For some of these younger athletes, it can be in the 140s or 150s. Even some of the older athletes can achieve that, but they have to be in very good shape compared to most folks in their 50s or 60s.
Back to the cyclists: a lot of them use a 45-second high-intensity phase followed by a 30-second low-intensity phase. That's one interval. Do a warm-up, do five to ten of those intervals, and then do a five-minute cool down. You're talking about 20 to 30 minutes total for an exercise. You don't need three hours in the gym to do these things.
Now, are there other ways to do this? Yes, you can run, you can go uphill, you can do what's called hill intervals, and each of these has a slightly different component. I saw an ad once that said, "It isn't that diabetes runs in my family; it's that nobody in my family runs." I get it; I understand, and that's certainly part of the process. But again, I think as a culture, we've gone too far to the other side. We think everything is lifestyle, and while lifestyle is very important, we forget about the biology and the genetics. Thank you.