HIIT (high intensity interval training) has gained popularity over the past years, but it remains one of the most misunderstood forms of training.
I'm a fan of including high intensity interval training into my workouts, and many of my clients workouts when appropriate.
But HIIT is a perfect example of how too much of a good thing can be a negative thing.
Honestly I get a mini high from a good, efficient HIIT workout . You know that sweaty feeling of satisfaction? It can be almost addicting.
But after 10+ years training women, and lots of research I believe we need to integrate HIIT into our routines MINDFULLY.
Let's start with how often you should be doing HIIT...
You should not be doing more than 2-3 days a week. Two days is typically more appropriate for most people (and their fitness goals.) Overtraining can happen more easily with HIIT training vs other types of less intense workouts. And lead to a slew of negative consequences that can mess with your body.
What are the PROS & CONS to HIIT training ?
- Can improve metabolic rate - metabolic rate helps you burn more calories through the day.
- Helps decrease body fat, and build lean muscle.
- Improves oxygenation (the muscles ability to use oxygen.)
- Saves time. It's an efficient way to move your body and hit multiple muscle groups in less time.
- May reduce resting blood pressure.
- It can make you feel great.
- Can seriously raise your cortisol. Our cortisol (stress) level effects so much- they impact our hormones, sleep, mood, hunger ... the list goes on. When you do a HIIT workout your body can easily enter fight or flight mode. This is something you might not recognize while you're working out, but the feeling lingers and can spike a stressor response. More on this below...
- Longer recovery time vs lower intensity workouts.
- Increased risk of injury - HIIT tends to involve a lot of jumping , and bouncing. Both can increase the chances of knee and ankle injuries in particular. This is especially true if you are deconditioned.
- Can cause bloating or digestion issues for some.
- Could lead to burnout.
- Could increase joint pain.
Provided you are physically ready for higher intensity training it's still a highly beneficial part of a fitness routine.
To me the biggest drawback for women is the pesky cortisol issue. When we're stressed nothing works at an optimum level. If we're already mentally or physically in a stressed state (and let's be real these days that's tougher to avoid) we add onto the existing issue. Too much intensity can can cause lasting anxiety after our workouts.
One of the biggest benefits to exercise is stress relief so why would we reverse that benefit?
Okay, how do you plan your HIIT workouts?
For myself and for my female clients I like to look at a few key factors...Do you have a stressful work week coming up? How much sleep are you getting? (little rest + hiit isn't a great combo.) It's also important to factor in where a woman is in her cycle. Then plan accordingly.
You are better off doing your HIIT workouts on the days you are more rested, and less anxious. Research shows that women's hormones right before and on their period may respond better to lower intensity workouts (think pilates, yoga, walking, strength training.)