Resistance Training Effect on VO2max

Increased VO_2max is a major adaptation associated with aerobic training. Responsible for this change is primarily the increase in maximal Q that comes about with long-term (6-12 months) cardiovascular training. ⁴ Increased stroke volume (SV is a factor of Q) accounts for the increased cardiac output.

Another adaptation to aerobic training is an increase in size and number of muscle mitochondria. As a result, more O₂ can be extracted from circulating arterial blood, which will increase a-vO_2diff. Since a-vO_2diff is a factor of VO₂ as evident in the Fick equation, increasing a-vO_2diff will increase VO₂.

Resistance training does not effectively improve VO_2max, even with circuit training methods. ⁴ Furthermore, since O2 extraction is generally not improved with resistance training, a-vO_2diff does not increase. This may be due to the decrease in mitochondrial density and conversion of fast oxidative-glycolytic (type IIa) to fast glycolytic (type IIb) that results from resistance training.

References

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VO2 Before and After Endurance Training

The ability to take up oxygen during exercise (VO₂) is a function of cardiac output (Q), which is the volume of blood pumped throughout the body per minute and the arteriovenous oxygen difference (a-vO_2diff), which represents the volume of oxygen extracted from the blood. These two factors are represented in the following equation for VO₂, known as the Fick equation:

VO₂ (ml^.min^-1) = Q x a-vO_2diff

This equation is very useful in understanding the relationship of each measure to one another and in getting a better idea of how exercise may affect each.

Assuming a 3-month aerobic training program is completed, post-training VO_2max will have increased from the pre-training value. Pre-training cardiac output and a-vO_2diff values at rest will be similar to the resting post-training values. However, the maximal values of these two factors will be higher post-training. Basically, the physiologic adaptations from this type of training program increase blood flow and O₂ extraction, which collectively factors into increasing maximal oxygen uptake.