So, picture the scene, its the end of January and you, along with thousands of others across the UK, are battling hard with your weight loss goal. As per usual for January, the gyms are packed with members and it never ceases to amaze me how busy the CV machines are (particularly with women). Yet, when I look around at how people are working out I often wonder just how effective their sessions are for a weight loss goal?
I have had more conversations than I would care to remember about how to train effectively for weight loss, so I thought I would share my views with you on how high intensity training, or interval training, can help start to blast away body fat!
So, why train at high intensities when the vast majority of machines in the gym have you working at a lower intensity if you choose the Fat Burning Zone?
This is largely based on an individuals Excess Post Oxygen Consumption or the ‘After Burn’ effect - which is whilst exercising at a higher intensity your body will use a lot more of it's glycogen stores for energy, which after exercise will need to be replenished. This replenishing process requires energy and as the demand upon the body is now no longer high, it has time to utilise the Aerobic Energy System thus breaking down fat stores along the way. So you continue to burn fats for longer after a higher intensity workout session.
Based on this fact, the aim of your high intensity, or interval training session, should be to burn more total calories during the workout and not to worry too much whether these are from fats or glycogen. The higher the intensity you work at the more total calories you burn off with more glycogen stores used so more to replenish after the exercise session has finished. Intervals allow the body to cope with a high intensity session as recovery periods are built in.
Why then, is the Fat Burning Zone at a lower intensity? It boils down to this - when you workout in this zone (which is 60-70%) a higher proportion of total calories burned will be coming from fats, so you are burning more from fats than you are from glycogen. However, the total number of calories burned at the end of the session will be lower due to the energy requirements being less demanding.
Take a look at these 2 examples to see what I mean:
Session 1 – the client completes a 20mins workout on the x-trainer at 60% Max HR and burns a total of 150 calories. A high percentage, say 60% of those calories would come from Fats and 40% from Glycogen. This means the client has burned 90cals from Fats and 60cals from Glycogen.
Session 2 – the same client completes a 20mins interval session on the x-trainer whereby the heart rate fluctuates between 60% (base) to 80% (peaks). The total number of calories is now showing at 250 as the demand is much greater. This time only 40% of those were from Fats (100cals) and 60% are from Glycogen (150cals).
Yes, the % from Fats has decreased but in reality the actual number of calories is still higher than at the lower intensity. Now couple this with the fact the client has more glycogen stores to replenish and what do we use as energy to do this – yes you got it FATS. So, if you weren’t already, have I managed to convince you that higher intensity interval training should be part of a weight loss programme?
Obviously, it goes without saying you will need to build your client’s fitness level up in order to work them at a high intensity and of course if they have a medical condition then always follow the guidelines. However, you can still use interval training at lower intensities too.
So here's what I suggest you do:
1, Workout the high intensity % at which you can work at and where your comfortable pace is for the base %.
2, Plan how long your can sustain the peak intervals for and how much recovery time you need in between. If you don't give yourself enough recovery time your overall time will reduce which in turn will reduce overall calories used.
3, Choose the exercise mode – this doesn’t have to be on a CV machine, you can do just the same with a circuit based resistance approach. Remember it is about getting the heart rate up and total calories burned.
Good luck guys!
Member since: 16th February 2016
Jon Morgan is a fitness expert and transformation specialist from Eastbourne ( East Sussex, UK ). Having worked with professional athletes and everyday people Jon uses his innovative techniques, education...