Interval Training vs. Steady State Cardio

More cardio means more weight loss, right?

One of the most common ways for someone to think they can lose weight is to join a gym and go hit the treadmill or elliptical everyday for an hour or more. This is one of the biggest myths about losing weight there is. When used effectively, cardio is a tremendous weapon to help you burn fat. But when used improperly, it can actually make you lose muscle, slow down your metabolism, and make your weight loss hit a major plateau.

Here is what happens to your body when you do lots and lots of cardio….

First, your body is programmed to adapt to any kind of new stress that you put on it. If you lift weights, your muscles will adapt and get stronger. Cardio is the same way. When you do lots of cardio your body adapts by getting more efficient at the activity.

For example, if you go outside and run 5 miles for the first time in years, it will feel incredibly challenging. You will probably struggle and will feel very tired afterwards. But if you do that same 5 mile run 5-6 days per week for the next 3 months, it is going to be significantly easier than it was before.

This is good right? You are in better shape and you are burning lots of calories by running so much. However, there is a downside to this type of training. The more your body adapts to doing lots of cardio, the more efficient it becomes. In this example, the running is much easier than it was before, therefore your body will not need to use as many calories to perform the task.

The same applies to doing a long cardio workouts (45+ mins) on a stationary bike, and elliptical, treadmill, etc.

But, there is more. One of the ways your body becomes more efficient at doing cardiovascular work is by becoming smaller. This means likely losing a certain amount of body fat AS WELL as lean muscle mass.

Having lean muscle mass is the absolute best weapon you will have in the weight loss process. Muscle tissue is very energy demanding, so it uses a lot of calories just to function. When you lose a lot of muscle you slow down the rate that your body uses calories (your metabolism).

Suddenly, you have done lots of cardio for a few months, you are better cardio shape, your weight is down a little, but you have also burned a lot of muscle in the process. In this case, you have actually slowed down your metabolism and your body will likely respond by adding on extra pounds very quickly.

Cardio is great for weight loss, but only if you use it in the right way.

So what is the best solution?

First, you need to do cardio. It should not be taken out of your routine.

Second, you need to do strength training. Not just getting on a few random machines and doing high reps with low weight. You need to challenge your muscles with strength training so they have a reason to maintain what muscle you have.

Third,  you should incorporate interval training cardio. This basically means that you alternate periods of very high and low intensity. For example, if you are running a track you may spring for 30 seconds followed by doing a walk for 90 seconds. You repeat this 6-8 times. This takes you way out of your comfort zone and makes your body have to recover afterwards. Recovery takes extra energy (this is known as the “afterburn effect”, which refers to your body still burning calories after your workout is over).

A lot of fitness professionals out there will say that interval training cardio is the only cardio anyone ever needs to do.  In reality, I think that a mix of interval training and same speed cardio is the best option. If you only ever do interval training you run the risk of burning out your central nervous system, and if you only ever do long cardio workouts you run the risk of overuse injuries.

Interval training workouts are great – you can get an incredible workout in under 20 minutes. However, this comes with a little bit of “fine print”. The only way you can do a cardio workout in under 20 minutes and get an incredible benefit is if you are working insanely hard. Imagine sprinting outside for 30 seconds straight and repeating it 8 times.  You would be very winded and exhausted afterwards.

If you do a cardio workout like this and only give a so-so effort when doing the 30 second sprints, you are not going to get much of an overall benefit. Sure you will burn calories, but you are basically just doing a shorter cardio workout. The intensity needs to be there or interval training will not be an optimal way of doing cardio for weight loss.

In the end, a mix of interval training, same speed cardio, and strength training is the best exercise combination for fat loss.