Re:
The Hitch said:
Basically a thread to discuss why people around the age of 40 have been so succesful at sport over the last few years. In cycling we have had Horner win a gt at age 41 and 8 months of course and a bunch of guys around 38, 39 going as strong as they ever did.
In biathlon Bjorndalen won an individual olympic gold age 40. In Ski Jumping, Kasai won silver age 41 and 7 months despite being not being a top performer in the sport for 20 years.
Why is this happening? Is it just a coincidence or are drugs responsible for this? If so, why are older athletes benefiting more now than they did before?
In theory, barring career ending trauma, the body should be able to keep going, and keep progressing with age. There is nothing about training in itself that weakens itself over the long term, besides any mental exhaustion, maybe.
So the physiological factors that do impair performance are about age, not fitness. There is a changing hormone levels:
THE mechanisms responsible for biological aging have not been clearly delineated, as aging is a complex, multifactorial process with a high degree of individual variability. It is believed that a major portion of age-related changes are a result of lifestyle and environmental influences, which may explain why some individuals age more successfully than others (1). It has been well documented that there are significant changes in endocrine function with increasing age. Levels of anabolic hormones such as testosterone, growth hormone, dehydroepiandrosterone (DHEA), and estrogen have been shown to decrease with age (2)(3)(4)(5). Reduced levels of anabolic hormones may be responsible for many of the changes in body composition and loss of function that are associated with aging. In men, age-related changes in insulin-like growth factor 1 (IGF-I) and testosterone have been shown to be significantly related to muscle mass (6), and many of the changes in body composition that occur with aging are similar to changes observed in subjects with growth hormone deficiency (4). Females experience a similar decline in anabolic hormones (3)(7), and it has been shown that quadriceps muscle function is significantly correlated to serum IGF-I and the sulfate conjugate of DHEA in elderly women (8). There is also some evidence that loss of estrogen after menopause accelerates the loss of muscle mass and bone mineral density in female subjects (9), and low levels of testosterone have been shown to be a limiting factor in strength and muscle development in older female subjects (7).
In addition to hormone stuff, there are biomechanical changes. Muscle elasticity changes, and the way the body changes elasticity also changes. Learned movement patterns are fossilized. Some of this is due to hormone changes, but it also comes from a sum of parts changing the way the body adapts to exercise stress. Armature athletes run the risk of physical damage from bad movement, damaged cartilage and arthritis, but let's ignore that for elites.
But a big piece is mitochondria dysfunction. The mitochondrial theory of aging is the idea that over time, various processes damage mitochondrial DNA. The ability to make new mitochondria weakens, and so does the ability of those mitochondria to produce energy.
It may read like a lot of gibberish, but you can figure out that it is talking about decreased gene expression and function with age. But it is well explained in the podcast I linked at the bottom (Author is the guest on the podcast). (It is a great podcast in general, and would interest a lot of the arm chair scientists like me on the forum).
A decline in skeletal muscle mass and function with aging is well recognized, but remains poorly characterized at the molecular level. Here, we report for the first time a genome-wide study of DNA methylation dynamics in skeletal muscle of healthy male individuals during normal human aging. We predominantly observed hypermethylation throughout the genome within the aged group as compared to the young subjects. ... Our findings highlight epigenetic links between aging postmitotic skeletal muscle and DNA methylation.
http://www.ncbi.nlm.nih.gov/pubmed/24304487
Check out episode 49:
http://guruperformance.com/consulting/podcasts/
So on to doping...
The first problem can be solved with steroid and hormone supplements. But Hitch's question is a good one when he asks "If so, why are older athletes benefiting more now than they did before?" I think that the specific issues of aging are better identified, and better interventions have been designed. Even if the published science does not know everything (and it knows a lot more than it did several years ago), the trial and error of practitioners, athletes, coaches and doctors will always figure it out first. We may have seen experimentation in age-related hormone/steroid doping for 40 years, but they only "got it right" recently.
Biomechanical stuff can also be better addressed than in the past. If Hinault had seen Dr. Müller-Wohlfahrt, he probably could have ridden for several more seasons.
But that last piece, mitochondrial dysfunction, is a little different. The science is newer than hormone stuff, but it is also less intuitive than hormone stuff. The science knows that resistance training can be a good intervention to stimulate satellite cells' (with higher quality mitochondrial DNA and function) function, to cause more mitochondria production in the muscle cells. A lot of older athletes avoid strength training, prioritizing more specific exercises when they feel their body has less capacity for different stresses.
I don't understand the science well enough, but I don't think traditional doping would be helpful in this case. They're good for their anabolic or catabolic effects, but that's not what we're looking for out of the resistance training in this case.
Effects of age and unaccustomed resistance exercise on mitochondrial transcript and protein abundance in skeletal muscle of men.
http://www.ncbi.nlm.nih.gov/pubmed/25695287
Regulation of mitochondrial biogenesis
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3883043/
As with anything exercise or performance, it is not a yes/no or a this/that. It's complicated. We know what Horner was up to thanks to his passport, but what allowed that to work, when it wouldn't for other 41 year olds is still a mystery. It's possible that some of the older athletes mentioned already could be clean, or not.