Cardio Before Weights: Which Should You Do First?
- Fit Therapy of Texas
- 9 hours ago
- 3 min read
One of the most common questions our trainers hear is:
"Should I do cardio before or after lifting weights?"

The answer depends on your goal, but if your primary objective is building muscle, getting stronger, or losing body fat while preserving lean muscle, the evidence points to lifting first.
Why Lifting Before Cardio Matters
Many people start their workout with 20 to 30 minutes of cardio because they believe it burns more fat. In reality, your body primarily uses glycogen during higher intensity exercise.
Glycogen is the stored form of glucose found in your muscles and liver. Think of it as your body's premium fuel source for strength training and explosive movement.
When you spend 20 minutes running, cycling, or using the stair climber before lifting, you begin depleting those glycogen stores. Then, when it's time to lift heavy, your muscles simply do not have the same fuel available to perform at their best.
Less Fuel Means Less Strength
Research supports this concept.
A study published in the Journal of Strength and Conditioning
Research found that performing endurance exercise before resistance training significantly reduced lower body strength performance, with some measures decreasing by as much as 23%.
The chain reaction looks like this:
Less glycogen available
Reduced force production
Lighter weights lifted
Less mechanical tension on the muscles
Smaller stimulus for muscle growth
Over time, this can limit both strength gains and muscle development.
What About Fat Burning?
This is where many people get confused.
Fat loss is determined primarily by your overall calorie balance over time, not by whether you're burning fat during a specific workout. However, workout order can influence which fuel source your body relies on.
A practical strategy for many people is:
Lift weights while your glycogen stores are full.
Perform cardio afterward, when glycogen is lower.
Recover well with proper nutrition and sleep.
This approach allows you to maximize strength performance while still receiving the cardiovascular and calorie-burning benefits of cardio.
Does That Mean Cardio Is Bad?
Absolutely not.
Cardiovascular exercise is one of the best things you can do for your heart, lungs, blood vessels, and long-term health. Resistance training and cardio each provide unique benefits, and both deserve a place in a well-rounded fitness program.
The key is matching the order of your workout to your primary goal.
Goal: Build muscle or strength? Lift first, then do cardio.
Goal: Improve endurance for running, cycling, or a sport? Cardio first may be the better choice.
Goal: General fitness? Either order can work,but prioritize the type of training that matters most to you.
