A 2018 study review found intense cardio such as HIIT sessions have minimal or negative effect on muscle loss, while a review in the journal Sports Medicine found that lifting weights and running at the same time (not literally, obviously, but as part of an overall plan) found that cardio might have a negative effect ...
No. Your body will not burn muscle. All it would do is strengthen your heart, allowing it to pump more efficiently and get oxygen to your other muscles faster.
Running does not have any catabolic effect - it does not negatively effect muscle growth. It burns a few calories so you've got to account for those. And it might make you a little fatigued which might impact on your ability to execute your lifts.
No, doing a reasonable amount cardio after weight training will not hurt muscle growth as long as you supply your body with enough nutrients and building blocks to grow (especially protein).
If you do cardio first, you will deplete some of that glycogen, decreasing your energy. And that will make weight lifting more challenging.” Cardio relies on a mix of glycogen and fat for fuel, he added. You burn glycogen when you lift weights, so if you do cardio afterward, your body has to burn more fat for fuel.
“Numerous studies have shown that concurrent training (cardio and strength training together) may result in decrements in strength, power, and muscular hypertrophy, while other studies show that adding cardio to resistance training may not inhibit strength or muscular gains,” says Hart.
Ensuring that you are eating the recommended amount of protein and fuel for your activity level will help maintain muscle mass and avoid any loss. Getting plenty of restorative sleep is key to avoiding muscle loss. Sleep helps to reset the body and provide enough energy for your next workout.
You will have stronger legs from running
When we run, we use all the muscles in our legs, big and small. If you are new to running, you might be surprised by how quickly you start to develop lean muscle in your legs and the speed at which you build endurance.
For some reason, the myth persists that cardio leads to muscle loss. But the truth is that cardio can be a crucial part of a well-rounded muscle-building programme, helping to boost mass as well as offering plenty more benefits to athletic performance and overall health.
If your goal is better endurance, do cardio before weights. If your goal is burning fat and losing weight, do cardio after weights. If you want to get stronger, do cardio after weights. On upper-body strength training days, you can do either first.
Change the intensity of your runs
Sprint for a minute and jog for three — adjust times for your desired intensity level, and push yourself to see how long you can maintain this mix. Sprinting works fast twitch muscle fibers and will increase overall size.
Four to five days is the sweet spot for many runners. Generally speaking, running more often develops your aerobic system better and helps you run faster and farther.
Final Thoughts. In conclusion, it's completely safe and in fact, recommended to do cardio after leg day. Not only does it help with recovery, but it helps increase your performance, assists in muscle growth, and helps you keep your body composition on the leaner side.
It can be a good addition, but is not required for building muscle and losing fat. Adding cardio doesn't mean that it will guarantee results. The 20 minutes of cardio will help to burn 50 - 100kcal (if low-intensity) and 100 - 200kcal (if high intensity), so you can do it if you enjoy it.
Enhanced Cardiovascular Fitness: Aerobic exercise — like regular running sessions — contributes to a stronger, more efficient heart, improving circulation and lung capacity. This cardiovascular endurance is beneficial during weightlifting, as it allows for sustained effort and quicker recovery between sets.
Many running experts recommend running no more than four days a week. More than that, and all the repetitive impact may take a toll on these lower-body muscles.
The short answer is no—at least not in the same way that strength training can. You shouldn't expect that you can experience the same level of muscle growth by going on runs that you would by lifting weights. But there are some circumstances where you might see some muscle growth from running.
Risk of overuse injuries. "The biggest drawback to running every day is not allowing the body to recover properly", Mack says. That can prompt problems related to repetitive stress on muscles, bones and tendons, known as overuse injuries.
Due to this caloric expenditure, cardio is normally associated with the loss of body fat as well as muscle mass. But, can you run and still maintain your hard earned muscle? The simple answer is: yes, as long as your calories are matched and the proper type of cardio is utilised!
In fact, newer studies have shown quite the opposite could be true: cardio doesn't inhibit muscle gain and may even help it. “In recent years, the body of research evidence indicates that doing concurrent training does not interfere with hypertrophy following resistance training,” Rosenkranz says.
In athletics, a 'long distance' run is considered anything over 5k or 3 miles – and there are plenty of distances that qualify from half marathons right through to full marathons. If the furthest you run is 5k then try to stay at the lower end of the scale and move up to a 10k training plan.
Running, which engages your slow-twitch (type I) muscle fibers to carry you through sustained aerobic efforts, should always be done after lifting if building strength or muscle mass is your main goal.
Myth 4: Cardio kills muscle gains
Don't let this myth give you a heart attack! The truth is, you can do cardio when training to build muscle – done right, cardio can actually improve your lifts (not just your health). It's best to prioritize explosive cardio such as HIRT or plyo.
If we sidestep the issue of running injuries completely, which would really complicate this discussion, I would say that 20 mi a week or less would be easily sustainable by most people. Somewhere between 20 and 40 miles per week is where it would likely start to become an issue.