The Case Against Long Duration Cardio For Weight Loss

I received a great question this morning on cardio that I wanted to share on the blog. I think it addresses one of the biggest misconceptions there is about cardio workouts for weight loss….the faulty belief that more must be better! This couldn’t be farther from the truth. Before we get into why, here is the question I received.

“Shane, I’m doing steady state cardio on the elliptical trainer for thirty minutes and jogging on the treadmill for twenty minutes, each morning, Monday through Friday. After initially seeing a few pounds of weight loss I’m now not seeing any change on the scale or in the mirror. What would you suggest I do differently?”

There’s a lot to unpack here, but the short answer to the question is to stop doing the thing that’s not working! In this case, 50 minutes of steady state cardio, five times a week for the objective of fat loss. If more is not the answer, which it’s not, the only other option is to do less or to do something altogether different.

Let’s talk about how we get here in the first place.

There’s long been this idea that the more cardio you do, the more calories you’ll burn, and therefore by definition the more weight you’ll be able to lose. The first part of this statement is correct. The longer you do any physical activity the more calories you’ll burn during the activity.

However, the second part of the statement isn’t true. When it comes to burning fat it’s not a fact that the more calories you burn the more fat you’ll lose.

If weight loss was simply a matter of calories in versus calories out, a simple strategy of calorie restriction combined with long duration steady cardio would work perfectly every time. As most people can attest to, it’s just not that simple.

The reason is the human body releases stored fat for energy when the conditions are right both from an energy demand standpoint AND a hormonal standpoint.

Calories burned during the workout are far less significant than the energy expended AFTER the workout. The most effective exercise routines for fat loss are ones that create post workout caloric expenditure through something that’s called the EPOC effect (Excess Post-Exercise Oxygen Consumption).

To simplify things, traditional long duration steady state type cardio workouts (like the ones you’d do for 50-60 minutes) have very low EPOC because the caloric expenditure pretty much comes to a crawl once the workout is over.

There’s also little hormonal response from growth hormone, adrenaline and nor-adrenaline for example to serve as catalysts for fat loss. If anything, you’re far more likely for the adrenal glands to release cortisol during prolonged cardio workouts when under-fueled which is completely counterproductive from a fat loss and lean muscle standpoint.

This is an example of the law of diminished returns. Basically, the body perceives prolonged exercise without adequate fuel as a stressor and responds accordingly.

 Why the cardio misconception on weight loss?

I think one big reason for this cardio misconception is because a lot of folks can lose weight when they’re younger by doing tons of cardio like this and restricting calories. You may have been able to get away with this in your twenties and thirties, but when you get into your forties and beyond, natural hormonal shifts and changes in your metabolism make this a terribly ineffective strategy.

A much better strategy for fat loss goals would be to emphasize on working muscle for your primary exercise of choice. Sure, some cardio can be supportive of this, but you don’t need a lot. The priority should be on resistance training.

Now just to be clear. I’m not saying steady state cardio is without benefit, quite the contrary. There’s a lot of evidence in the research that confirms steady state or zone 2 type cardio routines are a key factor in longevity.

Do you need to do 50-60 minute sessions?

While some may disagree, I’ll conclusively say no. About half of that amount would be sufficient and it doesn’t need to be done so often. Two or three times per week working your heart and lungs with this modality of exercise can be very beneficial. But again, we’re talking about from a health and longevity standpoint, not a metabolic standpoint for fat loss.

The practice of doing lots of long duration steady state cardio routines burn up a lot of glycogen (stored sugar) which can contribute to cravings for replenishing it, thereby creating what we like to call in the fitness industry “sugar burners.”

This is the person who burns a lot of sugar with long duration workouts only to be slammed by sugar cravings afterwards that end up leading to over consuming carbs. It’s a cycle that repeats itself over and over, but fat loss is minimal.

For optimal fat loss results, I’d recommend the emphasis being on working muscle (resistance workouts) done 3-4 days each week. Thirty minutes of doing resistance training, if done properly, is more than sufficient.

From a cardio standpoint, I’ve found that ten to fifteen minutes of higher intensity cardio done AFTER a resistance training workout to be far superior to doing the thirty-to-fifty-minute versions of moderate steady state routines.

If you want to do the longer steady state versions of cardio for other benefits, then do these workouts on days when you’re not strength training and make sure to fuel sufficiently. Caloric restriction and regular long duration steady state cardio routines don’t mix very well. Especially for a middle age or older adult who’s already got enough stress in the mix.

Again, from a fat loss standpoint, you don’t need these kinds of cardio workouts anyways. Give me ten minutes working hard on stair climber over longer duration cardio any day when it comes to getting leaner.

Bottom line

If I were to sum it up it would something like this…

• Cardio doesn’t work very well for changing your shape when you’re over 40.

• Working muscle does work well for changing your shape (at any age).

• For optimal fat loss results, much shorter, but higher intensity cardio sessions would be done following resistance training.

• Cardio is great for health and longevity, but you need adequate fuel for doing longer durations.

If you’re over 40 and want to lose weight do this…

• Lift weights.
• Consume more protein.
• Drink more water.
• Get out of breath a few times each week.
• Move frequently (8-10k steps per day).
• Prioritize sleep and stress reduction.
• Eat God’s foods not man’s creations.
• Minimize or avoid toxins like alcohol.

Until next time. Be blessed.

Shane Doll is a certified Charleston personal trainer, strength and conditioning coach, and founder of Shaping Concepts Personal Training Studios. He has over 24 years' experience with fitness coaching and consulting and specializes in training programs for middle age and mature adults. If you live in the Charleston, SC area you can schedule a no-obligations consultation.