By Selina Campbell, PhD
Polarized model vs a Sweet-spot/threshold model
I often get asked when it comes to training, which way is better – Polarized model or a Sweet-spot/threshold model.
I know people want me to say the latter as the former involves 75-80% of Z1-2 time (boring!) whereas the latter involves going harder and working up a sweat all the time, but does it really help you get fitter?
The short answer is that for a while, either will improve your fitness – consistent training is the biggest thing you can do, so just getting moving on a regular basis will see fitness gains. However, countless research articles confirm that doing practically nothing but sweetspot/threshold training leads to at best, plateau, at worst burnout and over-training? Why? Because every single ride you are having to go reasonably hard. Which feels great for a while; you are working up a good sweat after-all! But doing each ride at 80-90% FTP has you breaking down muscle tissue and when this is all you do, you never get a chance to rebuild stronger.
Remember, the way you improve fitness is by placing a stimulus (training session) on the muscles and then it is in the RECOVERY that your body rebuilds you back stronger and better. No recovery = no chance to rebuild and improve. Further, at this intensity level your body can’t reply on fats as the major fuel source. Energy is required too quickly so it has to burn carbs, reinforcing that enzyme pathway and never allowing the fat burning to adapt. The result being that when you get out on the road for a long ride, you will be guaranteed to fade (at best) bonk (at worst) as your body has limited fat burning capability.
And think about it – if you never challenge your threshold and always ride below it, how do you realistically hope to increase it? Enter the polarized model! Riding at Z1-2 allows the body to develop the ability to burn fat as a fuel source, as well as increase the number of mitochondria in the muscles (these are the energy producing factories in the cells). It also increases lung capacity, cardiac output and can be a nice flush for the muscles after a hard session (more on that below!) I have my athletes break up the ‘boredom’ of an easy aerobic session by having them focus on doing bike drills so they also increase their pedalling efficiency at the same time – a double whammy of improvement! Mentally, it is so nice as well that you don’t have to dread every workout because you know its going to be hard.
The trade-off for the easy time is when we go hard…. we go HARD! VO2 max, up to 30 min total work time per session spent ABOVE threshold. Doing the easy sessions easy, allows us to really push these workouts! This way we PULL up our threshold from above and PUSH it up from below. We work both ends of the scale.
Less injury, less physical and mental burnout. You’ll get better longevity and a bigger threshold to show to your buddies! Whats not to love about that?! So, don’t get sucked into the ‘sexy’ threshold only plans that litter the online training platforms – contact us at TCR for a customized plan that will keep you fit, healthy and progressing your fitness in a safe way.