On the other side of the spectrum regarding mitochondria development is their density (the size of each mitochondrial). Like volume, mitochondria density can be developed with both slower and faster training sessions. However, mitochondria density is more effected by training volume — the more you run, the faster you will increase the density.
Unlike mitochondria volume, which can be developed infinitely, there is an absolute mitochondrial density that each individual can attain, usually reached after 8-12 weeks of training. Not surprisingly, this time frame usually correlates with when you start “feeling fit” during your training segment.
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