I’ve always wondered what sports science has to say about doing cardio after a weight training leg day.
Is it a good idea or not?
I decided to do the research, and in this article I share what I found out about cardio’s potential impact on strength & muscle growth.
Is it OK to do cardio after leg day?
Cardio after leg workouts has benefits.
A sports performance study demonstrated that performing moderate-intensity cardio in the form of indoor cycling significantly reduced the effects of DOMS, delayed onset muscle soreness.
The cycling was done right after the leg weightlifting workout was finished.
That’s good news we can certainly put to use, but keep in mind that that study was under specific circumstances.
And there are a number of variables at work that can affect whether cardio after leg day will be beneficial for someone or not.
So up ahead we’ll look at a few of those scenarios and also check out how a few strength coaches treat cardio in their training programs too.
Science resources included
As is my custom here on heydayDo, I will provide links to all of the relevant sports science & medical resources, clinical studies, and nutritional data used in this article.
Cardio on leg day, afterwards
Recapping the sports study I mentioned earlier:
- the cardio was done on the same day as leg day
- it was moderate in intensity & 20 minutes long
- it was done after the weightlifting
- DOMS pain severity was significantly reduced (1A)
Key point: the timing of cardio
There are two main benefits of doing the cardio after the lifting, not before:
* the pedaling stimulates blood flow to the damaged/stressed muscles, speeding up recovery & lessening the delayed soreness (1)
* the leg workout wasn’t impaired like it would’ve been had cardio been done prior to weightlifting**
** – Sports science has shown that cardio before weightlifting reduces the strength, power, velocity, & repetition ability of the person weightlifting. (2)
What about a cardio day after leg day?
Light/moderate cardio to stimulate blood flow to your legs and burn a few calories won’t interfere with your strength training goals, whether it’s on leg day or the day after it, or whenever.
Except before you lift.
And programming cardio on an off day (if you’re sure you need it) makes sense, as long as it’s there to complement your strength training program, not compete with it.
Don’t do too much cardio
However, be careful of going hog-wild with your weekly cardio amount.
Research evidence exists that shows how concurrent endurance training (i.e., frequent heavy cardio) reduces “gains in muscle mass, strength, and power”. (3)
Beware the concurrent training effect
Many strength & conditioning researchers are focused on what they call the concurrent training effect, which is the influence that endurance training (heavy cardio) has on resistance training (weightlifting), and vice versa. (4)
And though there isn’t a real cut & dry explanation as to why, it appears that the more time per week someone (who’s strength training) spends doing cardio, the more they lose their hard-earned gains. (5)
You can see that in the table below, taken from the study Concurrent training: A meta-analysis examining interference of aerobic and resistance exercises.
The flip side is true for runners who lift
It’s also been observed that weightlifting has a negative effect on running economy, which measures how efficient & productive a runner’s use of their energy is. (6)
Sports studies have shown that a runner’s performance is impaired for up to six hours following a resistance/strength training workout.
And if the runner is training both weightlifting & running on the same day, then their performance will be poorer than normal the following day too.
Other ways to reduce DOMS
Earlier I mentioned how delayed onset – muscle soreness is a common problem following leg day.
Well, I found some things that can help ease the pain (literally).
The head of the International Fitness Professionals Association recommends that, in addition to moderate cardio, the following remedies could be used to help reduce DOMS: (7)
- spot-on nutrition
- lots of water
- adequate sleep/rest
- massage or a foam roller
- keep workouts under 90 minutes to avoid a cortisol spike
More on foam rolling
Foam rolling has been proven to reduce the various negative effects of DOMS (8).
The protocol was 20 minutes of foam rolling every 24 hrs. following resistance training.
Here are a couple of other benefits foam rolling provides that have been found in sports science studies:
- it can increase the range of motion of certain muscles
- it can improve muscle performance both pre- & post-exercise (9)
Here are answers to a couple of the commonly asked questions regarding concurrently doing cardio & strength training programs.
Is it better to do cardio before or after a leg workout?
Sports performance studies have shown that cardio after a leg workout can be helpful, but that doing cardio before weight training on the same day can interfere with your muscle-building goals.
Studies demonstrated that cardio beforehand reduced the strength of the lifters thus stunting muscle growth, and that it fatigued them so their workouts were shorter than normal. (10)
What should I train after leg day?
People also ask advanced lifters “What do you do after leg day?”
It depends, which isn’t the one-size-fits-all answer some people hope for.
But it’s true.
Asking a few experienced weightlifters these questions will get you a few different answers.
Like I said, it depends.
So you’re likely to hear that after leg day:
- one person takes a rest day
- another does cardio
- someone else works out their other muscle groups
- another does abs & core
There are several factors that are unique to everyone’s individual workout plans that dictate what ought to be done after leg day:
- Days per week in the workout schedule
- Strength training program volume & intensity specifics
- Other athletic activities outside the gym?
- Quality of recovery, sleep, nutrition
Are you familiar with weightlifting training splits?
There are a lot of ways to program weight training, because there are different goals & experience levels amongst lifters.
A training split divides up your lifting schedule over the course of a week so your muscles can recover properly.
This includes your legs of course.
So you can put your leg workout wherever it best suits your schedule, your training program & goals, & your body’s ability to recover.
I wrote an article covering the most common weight training workout splits used by strength coaches, bodybuilders, & weight lifters of all levels.
You can read it here on heydayDo.
Strength & conditioning coaches
Here’s what a few strength & conditioning coaches do after leg day in some of their weightlifting programs.
I’ve participated in a couple of Jeff’s training programs.
And regardless of the changing volume & intensity over the courses’ several weeks, leg day was mostly followed by a rest day.
And typical cardio was not programmed, until a little was added in the final weeks.
(Note that the programs I was in were focused on muscle building, not his courses on athletic performance training.)
The well-published though anonymous “Jay” has two different lifting programs he freely provides his 200,000+ subscribers.
One is a M-W-F (or a similar 3 days/week) beginners’ routine that features two workouts that alternate, A & B.
So week 1 would be ABA, week 2 BAB, and so on.
The other program is an Upper/Lower 4-day split, working each half twice per week, with rest days in between according to your “life” schedule.
In both the 3-day & 4-day splits, no cardio is programmed or even mentioned.
So any day after a leg day is a day off.
- In the 5-day program, leg day finishes with cardio.
- In the 4-day program, leg day has cardio the day after.
- In the 3-day program, leg day is followed by 2 days of rest.
So as you can see, he uses three different approaches for programming cardio & leg day.
My “after legs” plan
It’s only worth a penny or two, but I’ll share with you what I’ve done over the past 35+ years while deploying a handful of different training programs along the way.
I almost always took a rest day after legs day.
It didn’t matter if I was on a 4-day workout split (M, T, Th, Fr), a 3-day full body, a 5-day Bro Split, or whatever other type of training schedule I was on.
The off days usually would include light cardio to get my legs moving for 15 minutes or so just to get the blood flowing in them, since they were always sore as heck.
Sometimes I’d do abs on those days too.
I only did/do light cardio, because heavy cardio training can interfere with muscle building success. (15)
Now that I found out about that study I mentioned earlier (where doing moderate cardio right after your leg workout helps reduce soreness), I think I ought to be doing that too.
I hope that my article on leg day & cardio programming is useful to you, and I wish you well on your fitness journey; let’s go.