How Much Cardio to Lose Fat/Build Muscle | Time Saver Gym Workout

How do you lose weight and build muscle at the same time?  And how often should you do cardio?

Losing weight is very different from losing fat.  You want to lose fat, not just weight.  In short, the combination of aerobic training + resistance training will lead to the most fat-loss while gaining muscle, and the longest lasting improvements in body composition.

Muscle mass matters. A lot.

Muscle helps you lose fat and stay lean.  The more muscle you carry, the higher your resting energy expenditure (REE or basal metabolism).  Muscle is constantly being broken down and re-constructed, or synthesized.  Your body uses energy to break down and remake muscle. How much energy? That depends on how much muscle you have.


Once you have your goals, figure out a schedule to accomplish them and give yourself enough time to healthily accomplish the goal, but not too long that you lose motivation.

An example would be, “My goal is to lose 20 lbs.”

1-1.5 lbs per week is fat loss at a healthy rate, so give yourself 20 weeks to lose 20 lbs (keeping in mind that weight loss is not linear, so there will be ups and downs)


Then, decide how many days a week you are going to do weight training.  The most important part of any workout plan is to create a stimulus for your muscles, aka. lift weights.  Weight training impacts hormones and metabolism positively, and also builds strength, structure and function that you can use for many years into the future.

Apply the “opposite rule” here (in other words, the opposite of what you were doing before that didn’t work). For example, if you were training every day, twice a day, then start your program with once a day, only 4 or 5 days a week and increase from there to give your body time to rest and recover.  If you were only lifting weights two or three days a week, double your efforts.


Now plug in your anaerobic or interval progression. Think sprints, burpees, bike sprints, ect.  Start with 1 interval training session a week for a total of 12 minutes each session, and work up to three, 20 to 30 minute sessions weekly.

The duration of your interval can be anywhere from 15 to 45 seconds and your rest is relative to the intensity and duration of your interval.

Sample intervals:

  • 15 seconds HIGH intensity work such as burpees or 100 m sprints at the track – 1:00 REST – Repeat until your total time is completed.
  • 30 seconds MODERATE-HIGH intensity upright bike sprints – 1:30 REST – Repeat until your total time is completed.
  • 45 seconds MODERATE-HIGH tire flipping or elliptical sprints – 2:00 to 3:00 REST – Repeat until your total time is completed.

Ideally do intervals/sprints after upper body days OR at a separate time from strength training. As the weeks progress, it’s better to move them away from your strength training sessions all together.


Now we’ve taken care of the components that get optimal results — the strength training and anaerobic work, only after that’s happened should you add a “cardio” component. In fact, some people may not need any cardio, as they are metabolic furnaces — genetically gifted machines who respond very well to strength training and anaerobic work. However, those who have had issues with their weight much of their life, and would not define themselves as genetically blessed or fortunate, will benefit from the additional cardio. But remember, it is progressive and part of the entire plan. If you are doing five 40-minute strength training sessions a week and follow each of those with 12 minutes of either steady state or interval training (anaerobic) “cardio” sessions. This results in much less total “cardio” time, plus more metabolism and hormone boosting strength training – thus, better results in less time!


Throughout this period, follow the evidence. Take regular measurements of body composition, athletic performance and health to keep track of how this works for you.   Aim for a combination of aerobic and resistance training and working out 5 hours a week for fat loss and cardiovascular fitness. This combo will also help lower dropout rates and will improve cardiovascular performance.

Be Realistic

Be Consistent

Strive for Progress