The Genetics of Fitness
A review article in this week's edition of Nature discusses research showing that genetics strongly influences how one's body reacts to physical exercise.
Apparently around 5% of people showed no improvement in oxygen absorption following a twenty week fitness program, and 'good cholesterol' levels declined in a third of participants. Reductions in heart rates and blood pressure varied widely, with a few people (out of 740 studied) actually demonstrating decreased performance after the program. However, the researchers rather cheerfully pointed out that none of the participants fared worse on all of the factors studied.
About half the variability between people could be explained by genetics - fairly typical for behavioural traits. This is not irrelevant to me right now, having discovered today that two weeks into my fitness program, my weight is unchanged. I blame genetics, although in my case olive oil may be a contributing factor.
This kind of genetic trait is fascinating, in that it underlies the ability of the body to adapt itself to the environment. In this way, fitness is rather like the mental capacity for learning. In 1895 James Baldwin published 'Mental Development in the Child and the Race' in which he pointed out that the capacity for learning can contribute to the process of Evolution, by facilitating the evolution of complex traits. Individuals able to modify their instinctive behaviour to take advantage of partially evolved traits will derive advantage from those traits and tend to fix the genetic variants responsible in the population.
However, the 'Baldwin effect', is not limited to mental learning. In principle, many systems where there is 'wriggle' room between the hard-wired genetic information, and the physiological outcome, can and do display a Baldwin effect. There are some beautiful examples in bacteriology.
I wonder whether the variability between people in ability to adapt to physical fitness requirements, might not be a snapshot of a process of Baldwin evolution in action.
Apparently around 5% of people showed no improvement in oxygen absorption following a twenty week fitness program, and 'good cholesterol' levels declined in a third of participants. Reductions in heart rates and blood pressure varied widely, with a few people (out of 740 studied) actually demonstrating decreased performance after the program. However, the researchers rather cheerfully pointed out that none of the participants fared worse on all of the factors studied.
About half the variability between people could be explained by genetics - fairly typical for behavioural traits. This is not irrelevant to me right now, having discovered today that two weeks into my fitness program, my weight is unchanged. I blame genetics, although in my case olive oil may be a contributing factor.
This kind of genetic trait is fascinating, in that it underlies the ability of the body to adapt itself to the environment. In this way, fitness is rather like the mental capacity for learning. In 1895 James Baldwin published 'Mental Development in the Child and the Race' in which he pointed out that the capacity for learning can contribute to the process of Evolution, by facilitating the evolution of complex traits. Individuals able to modify their instinctive behaviour to take advantage of partially evolved traits will derive advantage from those traits and tend to fix the genetic variants responsible in the population.
However, the 'Baldwin effect', is not limited to mental learning. In principle, many systems where there is 'wriggle' room between the hard-wired genetic information, and the physiological outcome, can and do display a Baldwin effect. There are some beautiful examples in bacteriology.
I wonder whether the variability between people in ability to adapt to physical fitness requirements, might not be a snapshot of a process of Baldwin evolution in action.
- sheikh X at 5:54 PM
2 Comments:
Perhaps you need to consider a change in diet, to complement your exercise?
I lost another kg this week - and I did not exercise at all because I was sick with flu...
I think my diet is playing an important part. I am eating three meals a day. No snacking, no junk food and 2 liters of water.
i figured by running 500 calories and day and eating about 200 a day less, i lose 3500 a day which is a pound a week. but yeah, there are a few things i could cut from the diet.
you lost a kilo being sick! i dunno dude - not sure i'm quite committed enough to take that route ;-) but 2L water a day is a good idea in any case. (and you know guiness is only 200 cal a pint... so 2L of that is a decent lunch and you're nicely hydrated for the day!)
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