This page gives a summary of some findings from research that has been conducted over the years:
Circuits that contain entirely of resistance exercises can also improve aerobic fitness. However, adding aerobic stations into a circuit training session will increase the aerobic benefit.
Circuit training is an effective training method to maintain aerobic fitness. Doing 8 – 12 weeks of circuit training based on resistance exercises with some aerobic stations has been proven to increase VO2max by approximately 18%. If your circuit training didn’t contain any aerobic stations, it has been reported that your VO2max would increase by approximately 5%.
Regular circuit training will lead to an increase in lean body mass and a decrease in fat. Circuit training with a resistance focus promotes muscle development and increases muscle mass and tone.
It has been proven that circuit training can result in strength gains of 10 to 30% over an 8 to 12-week programme where the weight is at 40 to 50% of your 1 rep max (1RM).
Studies prove that blood lactate levels increase significantly when performing circuit training, this indicates a greater anaerobic emphasis than aerobic. The production of lactic acid stimulates growth hormone release which will support muscle repair and hypertrophy.
Science of Circuit Training
It is generally assumed that circuit training will improve both aerobic and muscular fitness. However what is the scientific basis for this consensus, and what degree of improvement can you expect?