HIT has been a huge craze for a long time now. In this day, time is precious. People love the feeling of getting the most benefits out of as little time possible. That’s why the ’30 min HIT’ sessions have become such a thing of nearly every gym-junkies training. And as a runner - a 30 minute threshold run is much more enticing than a 60 minute medium-slow paced run. The press around HIT has added to this craze, pushing the fact youll get ‘fit fast’ and ‘loose weight quick’ from doing such sessions. It becomes an addiction. The endorphins after pushing your heart rate through the roof are like nothing else - they raise you so high that you start to crave that feeing every day. There is a time and a place to do HIT but I talk to athletes who go to a HIT class nearly every day.
That means every 24 hours they are pushing their heart rate to above threshold, they are putting their body under intense pressure, stressing out their hormone levels, crushing their adrenal glands and in response having a prolonged state of elevated cortisol in their systems. Cortisol is a ‘fight or flight’ hormone and there are many negative side effects to having an increased amount in the body.
In 2016 I stepped away from competitive running for 16-weeks to train for a charity boxing fight. Boxing training is very different to elite running. Every day I was working at at high-intensity level, compared to a running programme working at this state only 1-2 times a week. I was training 2-3 times a day every day for my fight. This was the hardest 16-weeks of my life. After the first month of boxing I lost my period. Never had this happened to me before while running. Although I was only boxing for 4 months, it took 9 months before I got my menstural cycle back. Not only was the stress hormone levels in my body causing interruptions with my period, my skin also broke out seriously, my hair was falling out and I began to get a twitching eye. My body was under constant stress for so long that I was beginning to break.
I have no doubts that it was the exceeding rate of my heart being elevated every day that caused these drastic changes in my body.
For those who are doing daily HIIT classes, your body will actually be under so much constant stress that it becomes detrimental to how you are internally functioning. Once you are in the fight or flight state, your body will want to hold on to any energy that you are giving it, and therefore you have the potential to actually hold more weight than you would if you allowed yourself a few days rest in between. Or even allow yourself a few days of getting LIT in.
LIT is my new concept for Low Intensity Training. As controversial as it may sound, getting LIT in will do more benefits for both the body and mind than smashing yourself in HIT every day. Go for a slow run, or a walk, or do yoga or even just sit and meditate. This allows the body to reconnect, replenish and lower your cortisol levels before your next HIT session.
When relating this to running, in my running programme I am working at a threshold state once or twice a week with the remaining days running at medium pace with my heartrate at about 60% of my threshold. These easier days allow my body to recover under very little pressure and allow my hormone levels to balance out.
I am always told by my athletes that they want to run the fastest they possibly can on every run they do. The reason no athlete should do this as over time their 100% effort will slowly drop to a 90% effort, then a 70% effort, then 60%. It is much more beneficial for the body and the mind to work at 100% 1-2 days a week and 60-70% on the other days.
The key to being a good runner is consistency, and pushing hard every day will extremely effect the likelihood of a long-term relationship with running.
So if you are a HIT addict - do yourself a favor and get LIT in too.