A few weeks ago I posted the picture below on facebook encouraging people that are looking to lose fat to spend their time more wisely in the gym. I advised lifting weights and high intensity interval training over spending hours out pounding the pavement or on the treadmill. Since then a lot of people have asked me the reasons for this so I want to go into a bit more detail.
Now before I go on I must mention that there are many benefits to doing cardio, both physically and mentally. I have massive admiration for anybody who can run the 26 miles in a marathon and I think it’s great that there are people who enjoy walking/running/cycling etc. This piece is purely about the effectiveness of these types of exercise with regards burning fat.
I’m going to use an example to illustrate what I mean and hopefully it will become a little clearer. This example was given to us on a course I did last year and it makes great sense.
We are going to use an ‘average’ male as our case study. When he steps on to the treadmill it asks him to input his weight, gender and age to establish his Basal Metabolic Rate (BMR). This is the amount of calories your body uses when in a rested state each day. He walks or runs on the treadmill for an hour and burns 300 calories. However in a rested state he would have burnt 140 calories so the cardio has actually only burnt 160 calories. We know that it 1lb of fat is worth approximately 3,500 so it would take 22 of these steady state cardio sessions to lose 1lb fat (assuming calorie intake stayed the same). Seems like an awful lot of work for 1lb of fat!!
Another variable which we haven’t factored in is Muscle Loss. Steady state activity places very little demand on muscle tissue and as the old saying goes – “if you don’t use it, you lose it”. This is very evident when looking at marathon runners (steady state) versus sprinters (high intensity, accelerative) in the picture. Muscle burns far more calories than fat does at a rested state. By continuing with this cardio regime our subject will lose muscle mass and therefore his BMR will drop. As a result he will have to do more cardio or eat less to achieve the same calorie deficit. This is a vicious circle and will result in any weight loss reaching a plateau very quickly.
On the other hand, if our subject was to lift weights and do high intensity interval training he would build muscle, which would in turn raise his BMR. An increased BMR means that even in a rested state he will burn more calories every day. In this scenario our client is losing fat, not just losing weight (made up of muscle mass).
Resistance and HIIT training is also more time effective. I recently did a little experiment on myself using a heart rate monitor to compare 1 hour of steady state cardio with 1 hour of resistance training. I jogged for one hour at a reasonable pace and burnt 450 calories. I did a 1 hour lower body weights session and burnt 1050 calories. This hasn’t even taken into consideration the calories burnt in the next 24/48 hours while my muscles recover and repair.
To summarise, if fat lose is your aim – lift weights, run fast, save time and get results J