When should you do cardio for the most fat loss?
If you are looking to maximise fat use for fuel then the best time to do cardio would be in a fasted state with low glycogen availability.
This is why many people like to do cardio first thing in the morning before breakfast. However just because you have used fat to fuel your cardio session, this doesn’t mean that you’ve used body fat. If you are a fit person who regularly does cardio then it’s likely your body has adapted to store fat in the muscle for quick use for fuel. These fat molecules in the muscle are called Intra Muscular Trialglycerides (IMTAGs) and it doesn’t mean your muscles are fat. It just means you are a more efficient machine. Ironically the fitter you get and the leaner you get, the harder it is to actually burn body fat in a workout.
Obese people actually are more likely to burn body fat in a workout as they lack enough of the enzymes in the muscle to utilise fat for fuel during exercise.
Does cardio limit your muscle gains?
Cardio work will not limit your muscle gains under normal circumstances however follow these rules to make sure.
Don’t do cardio before weights.
The overload that you get from weight training sends signals to your body to adapt to build more muscle. The receptor that the signal goes to is the same one that cardio signals go to for adaptions for endurance exercise. if you do cardio first then you may activate something referred to as the ‘Interference Effect’ whereby cardio can interfere with muscle gain signals and potentially limit muscle and strength gains.
Try to do cardio at a different time to weight training
To make sure there’s no interference effect do cardio a few hours before or after weights if you’re training on the same day. This will allow the receptor to be clear and free from interference from both signals.
How much cardio should you do?
If you are looking to maximise calorie burning then you should do as much cardio as you feel comfortable doing every day.
Remember that exercise is supposed to be enjoyable and if you start to hate cardio it will become stressful and this will associate a stress response with the activity. Negative thoughts will not help your body and mind in the long term so it’s best to find a cardio activity that you like doing rather than looking for the ‘best’ activity.
Is H.I.I.T better than L.I.S.S cardio
High Intensity Interval Training does have certain benefits.
- It burns a ton of calories
- It improves cardio vascular fitness
- It is short and time efficient
- If you’re using weights in a circuit it can be more fun than walking on a treadmill.
However it can be very tough and if you’re tired already from dieting it can be a tall order to then push yourself hard to do a HIIT session.
If calorie burn is the main goal – which is it for most people doing cardio in gyms – then you can burn the same calories in a Low Intensity Steady State cardio session. In terms of effects of fat loss, HIIT and LISS have no difference when calories are matched.
Watch the video or listen to the podcast to learn more about cardio and when is the best time to do it.