Often, I’m asked the question "which should I do first, aerobic or anaerobic exercises?" Personally, if my goals are to help reduce fat, I always start with aerobic exercises (cardio) before anaerobic exercises (weights). There are several benefits to starting first with aerobic exercises.
Starting with aerobic exercises is a great way to warm-up your body. By keeping your heart rate between 60-70% while you warm up, you’ll setup your body to start the calorie and fat burn right away. You will also start have a fresher body at the start, so your legs won’t be exhausted when you start.
Some great exercises to start with are:
This is a very low impact cardio that is easy to do. It’s safe for your legs and knees and will help strengthen them. It will also target your glutes. You can also control the speed and resistance to your own personal preference.
Walking is great, and incline walking is better. You will use more of your leg muscles (calves, quads, glutes, hams) and improve your endurance. If your goal is to start jogging, this is also a great way to build your legs up.
This is always important, as it helps to loosen muscles and encourage blood flow. With proper breathing, this can be really beneficial, especially to improve flexibility.
There is often the misconception that aerobic exercises before anaerobic exercises will actually tire you out, but the purpose isn’t to spend a long time doing the aerobic exercises, just enough to break a sweat and loosen your body and muscles up. If done correctly, 15-20 minutes of warm-up aerobic exercises will actually burn more calories than 15-20 minutes of anaerobic exercises.
As you gradually improve your aerobic exercises, you’re also improving cardiovascular system which will help with recovery and endurance when working out in the anaerobic zone. Your body will use oxygen a lot more efficiently, and you’ll notice your recovery time between sets will improve (decrease). This added benefit will also allow you to work out longer and thus burn more calories and fat over time.
If you do train anaerobic first, it will require a lot more energy to do aerobic training at the end. This could mean a less-than-optimal aerobic session as your body will have exhausted your energy levels. Plus, you may have not exhausted all your glycogen levels, as you may have “saved yourself” for the cardio at the end. In that case, the anaerobic training wasn’t as efficient as it could have been.
In the end, it’s really a matter of personal preference. If there is a lineup for cardio machines, or your gym partner prefers to train anaerobic first, then that will work. You could also do separate workouts, one day for aerobic, one day for anaerobic. As always, if your goal is weight and fat loss, burning more calories than you take in will burn fat down.