Why not? If you enjoy it, and want to stay overall healthy there is no harm in that. People like to separate cardio and lifting weights like they’re enemies of each other. The truth is, unless you're a bodybuilder looking to absolutely maximize your bulking phase (in which you’d lower or sometimes eliminate cardio just to optimize your caloric expenditure and muscle building signal towards muscle gain) there’s no reason to just intentionally leave it out.
Aerobic Capacity vs Workout Capacity
Whether your goal is to lose weight or gain weight, you should be resistance training. I don’t see any reason why anyone would want to lose whatever muscle they currently have on their frame (unless you're freakishly huge and don’t want it).
While yes, incorporating TOO much cardio during a weight loss phase can potentially burn through some muscle, or not optimize the signal to grow, that doesn’t mean you should throw it out completely. We clearly have the muscle building stimulus recovered. Are you working on your aerobic capacity? We all know that feeling of getting winded simply going up a flight of stairs. Or trying to keep up with our kids and having to gas out after 2 minutes. Some people just accept this at face value. Similar to losing muscle as we age, people just think this is what should happen to them as they get older. But it’s not!
You can simultaneously work on your aerobic capacity while you are building your workout capacity. Just make sure to have a balance. Having a minimum of 2-3 days of lifting with 2-3 days of cardio (HIIT, LISS, or NEAT), is a great way to get the best of both worlds. This will allow you to still reap all the benefits of jogging (increased mitochondria production, oxygen exchange, VO2max), while still building or retaining muscle.
The only thing you need to watch out for is an imbalance of one or the other depending on your goal. If you primarily want to focus on endurance (i.e. marathon runner, obstacle course racing, etc), then I would recommend spending more time on the running aspect throughout the week and reduce the resistance training to 1-2 days. If your goal is to build muscle, I would focus more on pushing heavy weight throughout the week and lowering the cardio to 2 maybe 3 days. That’s all there is to it.
Let’s not forget about NEAT
NEAT is basically all the activity you do that you aren’t aware of. When you’re just walking your dog, fidgeting, or moving to and from places. I like to look at it as all the movement you’re doing when you’re not in the gym. That right there should give you a glimpse into its effectiveness. You are only in the gym 1-2 hours of a day. That leaves 12-13 hours of extra time you could be “sneaking” in extra calorie burn.
This is an even better way to incorporate extra movement throughout your day while maximizing the muscle building signal or extra caloric expenditure for those with a weight loss goal. Instead of say 3 days of cardio running around town or on the treadmill, instead try hitting 10,000 steps throughout your day. Then, each week up it by 2,000 calories and see if you can still hit your goal. Hitting goals, and building a routine is just that - a routine. If we want to succeed at something, we have a higher likelihood of doing so when we can mix it into our daily lives. Step count allows you to do this. The best part is, whatever steps you can’t hit throughout the day, you can THEN add through extra jogging, or cardio at the gym. Again, this isn't’ an EITHER OR situation. Both components are hugely important for your fitness and longevity throughout your years.
