Are you one of those people who love to combine your cardio and resistance training together? You may have read that doing these two modes of exercise back to back can be detrimental to your strength and muscle gains.
But is this really true?
Is it more beneficial to do cardio before or after resistance training?
Let’s take a look at some recent research that directly answers this question at a cellular and molecular level.
Background
Skeletal muscle is highly adaptable and responds differently to various types of muscle contractions. We know that high-intensity muscle contractions, such as those involved with resistance exercises enhances a muscle’s size and strength [1].
Low intensity muscle contractions like those performed during endurance exercises (e.g. running) cause increases in oxidative capacity and glucose uptake [2].
Concurrent training, performing resistance training and endurance training together, is widely used in exercise prescription to simultaneously enhance muscular strength and cardiovascular function.
There is mounting evidence suggesting combining the two modes may hamper strength and muscle size adaptations to resistance exercise [3], although some research has shown differently [4].
Interestingly, recent work in humans reported that endurance exercise performed prior to resistance exercise increased muscle mass more than performing resistance-only exercise [5].
In this research, the group performing endurance exercise at about 70% of VO2 max, completed the session 6 hours prior to performing resistance exercise.
There is a certain molecular response that occurs after resistance exercise that differs from endurance exercise.
During concurrent training, the endurance exercise molecular response may differentially affect resistance exercise induced molecular responses, depending on the exercise order.
A recent study investigated whether endurance exercise before or after resistance exercise may differentially affect the molecular response [6].
Highlights of this research
This is the first study to show that the order of endurance exercise and resistance exercise in concurrent training affects resistance exercise induced muscle protein synthesis.
Muscle protein synthesis is the ability of your muscle to utilized amino acids and make new muscle proteins, eventually accumulating to an increase in muscle size.
Endurance exercise performed after resistance training resulted in decreased muscle protein synthesis, unlike the opposite exercise order.
These data provide important new information regarding the interaction between resistance exercise and endurance exercise induced molecular and protein metabolic responses.
Key take home points
A molecular signal which acts as a negative regulator of muscle protein synthesis was significantly elevated 3 hours after resistance exercise when endurance exercise was performed following resistance exercise.
This means that there is less muscle growth when endurance exercise was performed after resistance exercise.
Prior activation of this negative regulator of muscle protein anabolism by endurance exercise before resistance exercise does not affect muscle protein anabolism.
This research demonstrates that endurance exercise performed directly after resistance exercise is more detrimental to the anabolic response that occurs from resistance exercise than when endurance exercise is performed directly prior to resistance exercise.
Keep in mind that this is one study and it was done in an animal model. I think more research is needed and over longer periods of time to see the effects on muscle hypertrophy and strength.
This research indicates that if concurrent training is absolutely necessary; it may be best to conduct cardio exercise prior to resistance training.
To be really conservative and prevent and detrimental effect on muscle protein synthesis, I would also recommend nutritional support like a fast-absorbing carb such as Hyperade and whey protein isolate such as Whey-Iso between your cardio and resistance training sessions.
References
1. Ogasawara, R., et al., mTOR signaling response to resistance exercise is altered by chronic resistance training and detraining in skeletal muscle. J Appl Physiol (1985), 2013. 114(7): p. 934-40.
2. Hoppeler, H., et al., Endurance training in humans: aerobic capacity and structure of skeletal muscle. J Appl Physiol (1985), 1985. 59(2): p. 320-7.
3. Hickson, R.C., Interference of strength development by simultaneously training for strength and endurance. Eur J Appl Physiol Occup Physiol, 1980. 45(2-3): p. 255-63.
4. Mikkola, J., et al., Neuromuscular and cardiovascular adaptations during concurrent strength and endurance training in untrained men. Int J Sports Med, 2012. 33(9): p. 702-10.
5. Lundberg, T.R., et al., Aerobic exercise does not compromise muscle hypertrophy response to short-term resistance training. J Appl Physiol (1985), 2013. 114(1): p. 81-9.
6. Ogasawara, R., et al., The order of concurrent endurance and resistance exercise modifies mTOR signaling and protein synthesis in rat skeletal muscle. Am J Physiol Endocrinol Metab, 2014. 306(10): p. E1155-62.
