Current exercise recommendations endorse a mixture of strength (resistance) training and endurance (aerobic) exercise. Resistance training is important for building strength, as well as increasing lean body mass and bone density, while endurance exercise improves aerobic capacity and vascular flexibility. Many active people engage in both types of training, for instance lifting weights twice a week and running or cycling two to three times a week. Today we are going to discuss the effects of carrying out both strength and endurance training concurrently and how to get the most benefit from such a program.
First, the good news for anyone who considers themselves primarily an endurance athlete is that strength training has been shown to have little to no negative impact on endurance performance. In fact, concurrent strength and endurance training has been shown to improve performance in both short- (<15 min) and long-duration (>30 min) endurance activities, predominantly via improvements in neuromuscular function and economy. (See our previous blog post "Lift Heavier to Run Farther" for more details.) So, if your first love is an endurance sport like running, adding strength training to your routine is a no-brainer.
If, however, building strength is your number one priority, you may need to be careful about how you incorporate aerobic activity into your weekly workouts. This is because numerous studies over the last two decades have demonstrated an interference effect of concurrent strength and endurance training. Under this effect, those who follow a combined strength + endurance training regimen don’t see as large gains in strength, muscle hypertrophy, or power development as those who follow a strength training-only program. It remains unclear whether this interference is due to residual fatigue from endurance exercise reducing the quality of the strength training session, or whether the molecular responses to strength training are actually counteracted by endurance activities. Recent research has focused on whether the order of activities matters, and it appears that the answer is no. That is, if you combine strength training and endurance training into the same workout, the interference effect remains the same no matter what the order of the two activities (strength training first or endurance exercise first). Unfortunately, little else is known about mitigating the interference effect, including whether it’s better to alternate strength and endurance activities on different days rather than doing both in a single workout, or at what thresholds of endurance exercise (in terms of volume, frequency, or intensity) the effect begins to be apparent.
Few athletic endeavors, however, require an absolute maximal amount of strength at the expense of all aerobic conditioning. For most athletes and most recreational exercisers, a mixture of strength training and endurance exercise is still the best regimen for improving overall fitness as well as performance in a variety of sports, despite the interference effect. Those engaged in concurrent strength and endurance training still consistently achieve increases in strength, lean body mass, and aerobic capacity, as well as improvements in markers of health, such as lipid profiles and blood pressure. A program that involves strength training 2-3 times each week, supplemented with an endurance activity such as walking, running, or cycling 2-3 times each week (either on the same days as the strength training or on alternate days) is therefore an excellent routine for the vast majority of us.
If you’d like help designing and implementing a regular strength training and/or endurance exercise routine, contact us here.
Source: Fyfe, JJ, Bishop, DJ, Stepto, NK. (2014) Interference between concurrent resistance and endurance exercise: molecular bases and the role of individual training variables. Sports Medicine, 44(6): 743-762.