by Chad Kerksick PhD November 21, 2011 5 min read
How many of you have ever wondered what impact it might have if you did weights or cardio first when you go to the gym?
Maybe you burn more fat if you do cardio first or weights first?
Or maybe it negatively impacts your ability to improve your aerobic fitness or your strength?
An interesting article was published in the Journal of Strength and Conditioning Research that sought to provide an answer to this question (Oliveira and Oliveira 2011). The researchers had seven young men (around 20 years old) complete two sessions of exercise. Both sessions consisted of a resistance portion and an aerobic or cardio portion. The resistance portion utilized five exercises (bench press, squat, one arm row, lunges and shoulder press) and had the participants complete three sets for each exercise. The amount of weight used for each exercise was predetermined to be around 70% of the maximal amount of weight that could be performed for each exercise.
For most of the participants this resulted in them being able to successfully complete around ten repetitions and approximately 75 seconds of rest was given between each set of exercise and between each exercise. The cardio portion had individuals exercise on a treadmill for 30 minutes at 80-85% of predicted heart rate capacity or heart rate values that were likely between 165 – 175 beats/minute. Prior to each exercise bout, the subjects were tested for a number of markers related to recovery and fitness and were tested again for the first 60 minutes after they completed the combined exercise bout. The variables which were measured provided the researchers with an indication of recovery but also how many calories were being burned and to what extent carbohydrates and fats were being burned. The authors of this study concluded that the order or sequence with which cardio and weight workouts were completed did not impact any of the variables measured (Oliveira and Oliveira 2011).
What does this mean? Well for starters this is just one study in an area that involves several areas where changes could influence the results. For example, the intensity of the run, performing elliptical exercise as opposed to running or completing intervals are all common everyday fitness considerations that could change how the physiology of the body responds. Similarly, different weight lifting exercises could be completed that involved more or less complex movements, more or less weight could be used, the order in which the chosen exercises are completed and the amount of rest taken could all potentially impact how the body responds to the weight lifting portion of this type of workout. If, however, these findings are characteristic of how the body will respond, this suggests that you can complete your workouts in whatever order you prefer and don’t worry about it. For example, say you enter the gym at an extremely busy time and the weight section is crowded… you could hop on the treadmill and when you get finished hit the weights or vice versa. The results from this study suggest that the calories burned and/or energy expended is going to be similar regardless of how you break it down. From a flexibility and practicality standpoint, this is a great thing!
When looking at the research, a few other aspects need to be mentioned. The subjects used in this study were young and fit college-aged males. I would find it particularly interesting to see if the results of this study change if an unfit, overweight or obese population of men or women is used. One could argue this is a population where the study outcomes are just as or maybe even more important. It is possible that because of the differences in motivation, exercise tolerance and fitness, the results may change in a less fit or motivated population where one sequence is preferred over the other. Also, these authors did not measure any marker in the blood that would provide a better indication of much fat is being burned and the measures were only taken for an hour after the workout. It is possible that the sequence of exercise may influence how much fat is burned, which would likely be an outcome many people would find interesting. Lastly, a number of studies have been completed which demonstrate fairly conclusively that performing cardio before weights can negatively impact your ability to get stronger and develop power (Nelson 1990; Kraemer 1995). More so, these studies have also shown that doing weights before cardio can negatively impact your aerobic fitness and related performance (Nelson 1990; Kraemer 1995). These findings are important to consider, particularly if you have the desire to increase your strength and endurance performance. While more research needs to be conducted, previous research has suggested that short-term depletion of energy stores inside the working muscles are to blame for the reduction in strength and/or endurance performance (Leveritt 1999). The final point and this is kind of cool for you science types. Two studies have even reported that the sequence in which you perform an aerobic or weights workout can influence the extent to which different genetic material inside a person’s muscle is expressed, but again more research is needed (Coffey 2009; Hawley 2009).
In summary, the sequence with which you complete a typical workout session that involves both an aerobic and weight lifting component doesn’t appear to be an important factor when considering overall calories burned and how quickly you recovery from the combined session. While valuable findings, a number of additional points or questions still need to be asked to more fully explain the effects which occur. Other research has shown that if you have a particular interest in increasing your strength and power that performing your weights before a cardio session is preferred. Similarly, if you have aspirations to increase your aerobic fitness and improve your 5K time, it is best if you perform your cardio before weights. In closing, the mantra of “something is better than nothing” holds true in this instance. Just get to the gym and do so regularly and don’t worry about which type of workout comes first. After you’ve got your routine down and you have a specific goal in mind to get stronger or run faster, then worry about which workout comes first.