Is combined strength and cardio training bad?

Question

TL;DR: Is combining weights and cardio within the same exercise unwise or unproductive?

This video by Gravity Transformation talks about cardio during weight training and describes how combining the two in a certain way can help the goal of maximising fat loss, specifically:

PHA incorporates an element of cardio into your weight training routines by forcing your heart to work harder.

This ATHLEAN-X video, however, talks about HIIT and Tabata (albeit briefly) and criticises the use of strength training combined with cardio, specifically:

Be singularly focused; If you're trying to train for strength - train for strength; If you're trying to train for cardiovascular ... then do that, but don't try to combine the two because it becomes just stupid in the long run.

I am not sure if the second video is saying that the advice in the first video is actually wrong or if it is simply saying "do that type of training properly or don't bother."

I am not referring to this question or this one because I am asking if the two types of training should be used within a single exercise set at the same time at all, rather than on different days or for particular timings within a gym session.

Answer 1

Combining strength training with cardio in the same workout is sub-optimal. Each modality reduces the effective stimulus of the other by some significant but relatively minor fraction.

It's important not to misinterpret that statement, because it does not mean that combining them is "bad" or "stupid" or makes the workout "worthless". Such hyperbole is false and misleading. Don't trust someone who speaks in such absurd absolutes -- their advice is bad, stupid, and worthless.

One way to remember this is to thing about all the many, many people who get bigger, stronger, leaner, and fitter using mixed-mode training like kettlebells, circuit training with weights, and calisthenics. These kinds of training demand both strength-power and conditioning -- do you really think your body will be so confused by the presence of both that it won't adapt?

It's true that all other things being equal, you'll probably see better results in each performance category if you train strength and conditioning separately. But nobody said all other things are equal in your training! If you're forced to choose between running your 5k after your lifting session or not running at all this week, then you're almost certainly better off running. It may mean the training stimulus of your overhead press work in that session is blunted by 20%, and you run at 80% of what you would if you hadn't just lifted. But that's okay; it's more training stimulus than skipping the run.

Answer 2

I think the proper way to look at this is to determine what your goals are.

I've been on both sides -- at one point I was an elite endurance athlete. There were two head national team coaches. One felt like weight training was something you did if you were at the point of diminishing returns for endurance work. The other head coach wanted you to lift heavy in specific ways before your endurance work out 2-3 times a week. Sometimes so heavy that it was easy to be injured. Both had successes and failures.

The last few years I started lifting heavy. I had done so much endurance work over the years I didn't want to do it any more. And I got strong. Also ended up hurting my shoulders. I loved lifting heavy, but I know I couldn't do both, and I wish I'd dialed it back a couple notches. Due to Covid I stopped going to the gym (no one wore masks and a friend got diagnosed with Covid 3 days after I started going back there in the summer...so I decided to hit pause).

Due to Covid I've been back to endurance work. I've got weights which I often use, but its hard to find the time for 120 minutes of endurance work (rowing machine, bike trainer, or trail running) and also do 60-90 minutes of strength training. But if I were younger, I would probably want to do both.....but the mix of the two would be driven by what my goals were. If I wanted to be better at endurance, that would be 75-80% of my effort. If I wanted to be stronger, I'd flip that and make endurance work maybe 20-25% of my effort.

One of my first elite coaches had a saying...he had a very different approach than my prior coach. But rather than saying it was wrong, he said there a many paths to the top. The goal is to find the path that work well for you.

Answer 3

Delicate question. I am still trying to figurę out an answer for my own training.

What is clear for me is that combining the two during the same session is worthless. It does not bring any benefits endurance wise or strength wise EXCEPT if your sport requires such combination (CrossFit is the first example that comes to my mind). Then this is training for your sport setup/competition setup so that your body learns what it feels like. But this is not to induce adaptations.

Now the answer gets trickier if the question actually is ‘I train two times a day. Can I combine endurance and strength the same day and still get good adaptations?’

To answer, you need to go down the path reading current molecular physiology research. One of the first article I read that helped me is this one. You an also look for the textbook from Alex Viada ‘the hybrid athlete’.unfortunately, up to now, I still don’t have a yes or no type of answer.

Answer 4

Gravity Transformation says in another video that if you want to train both cardio and strength, to place the cardio as far away from the strength training session as possible. If you must train both on the same day, do the strength training first, to maximize set quality.

He adds that lower intensity workouts (e.g. walking) have a lower interference effect than higher-intensity cardio workouts.