HIIT WORKOUTS WON'T KILL YOU.

9 hours ago
4 min read

Cortisol seems to be on the top of everyone’s hate list right now.

Look, I get it. I also have a love-hate relationship with cardio. But please don’t be fooled by these false facts circling around the internet. I keep getting sent stuff from fitness influencers on how we shouldn’t do any sort of high intensity interval training (HIIT) anymore. We are spiking our cortisol! It’s making us fat! We are giving ourselves anxiety! (You get the idea.)

Please don’t fall for this.

Yes, high levels of cortisol are bad for you. If you are a highly anxious person or suffer from panic attacks, you understand how high stress affects your life and well being. However, there are benefits to cortisol spikes.

Skipping cardio is not going to help you long term.

Here's why:

When we spike our heart rate during an interval, this creates a stress response. When we recover after our interval, our body recovers. It’s essentially a rehearsal of our flight or flight reaction.

This is very similar to what happens when we are strength training.

When we are lifting something heavy we essentially rip up those muscle fibers. We’re breaking down that tissue, and it’s not when we’re exercising that we get the benefit. It’s during the recovery phase that all your little helper cells go in and repair that tissue and build it back stronger.

So that’s how you build strength. It’s not during the actual workout itself.

A HIIT workout works like this: You accelerate your heart rate for a set amount of time and then give yourself a solid recovery. Typically we repeat this for a certain set or reps. This is different from a steady-state workout like walking, paced road cycling, a slower / more endurance-focused workout like barre, Pilates, or Yoga. Think of a spin class where you sprint for 20 seconds, then recover for 60 seconds, then repeat.

The benefits of HIIT is increased metabolic effects along with a stronger cardiovascular system. You are going out of that aerobic fitness into the anaerobic fitness phase. I’m not gonna go into too many details, but there’s lots of metabolic reasons why we want to be doing that as far as burning sugar, fat and building an overall more active metabolism.

The same goes for cortisol. You actually get a ton of cortisol benefits from high intensity strength training for your mental health. It’s a rehearsal for a stressful situation. Imagine you are having a panic attack . What are you supposed to do? You’re supposed to breathe. When you feel breathless during high intensity training, we’re essentially teaching our bodies how to recover from stress. Then comes the flood of relief and calm post-workout. (Think runner’s high!) This is the hormonal response to exercise. It’s a beautiful thing you shouldn’t miss out on because some Influencer lied to you.

For me, someone with a ton of anxiety, I actually notice I feel way more Zen on the days that I do high intensity work. I am calmer, and I sleep way better.

Here’s the kicker… And here is why I think so much has gotten lost in the influencer crap.

If we don’t allow the full recovery and you are ending your class in that height and state and not including a cool down in your workouts or stretching, etc., and we aren’t letting the body fully recover.

If you aren’t taking rest days, you run the risk of overtraining. This increases your cortisol. If you aren’t stretching or doing a cool down, you aren’t recovering. I wouldn’t recommend that a person with high stress do more than 3 days of high intense work each week. I would certainly give them a rest day after or a different workout so they have the chance to absorb the benefits of the HIIT workout.

That’s when we can come into problems, especially for Moms!

If you are a mom with little kids, you are likely very stressed out. I don’t think we as a industry talk about how important sleep is. Many of my clients will get strength gains, feel amazing, but won’t see changes on the scale if they aren’t sleeping or suffering from chronic stress. (Hi from parenting a toddler.)

We need to build rest into our workouts. Some of this happens naturally during busy seasons. However, even when we are in a calmer routine, I would never have someone work the same muscle group in the same way two days in a row. We might do a hard push and then she’s gonna take a walk or do Pilates the next day. We might do interval training, then we might lift weights. Or will work one part of the body one day, one part of the body the other day, etc.

I also have a mandatory two-day rest day each week. I also like to build in my workouts for them based on their menstrual cycle. We push when we’re feeling like we have more energy , then scaling back when we aren’t feeling up for exercise anyway

When I program for my clients, I make sure that they’re having a steady-state day during their week. Getting steady-state workouts in, whether it’s walking their dog, or going for a gentle bike ride, are great for mental health and aerobic fitness. However, HIIT workouts can be more time effective and have more long-lasting metabolic effects.

Please do not feel overwhelmed by this. This is where I'm happy to help you. I have been working with pre-and post for about two decades at this point. You can book a 30 or 60 minute session with me and we will map out exactly how to build work and recovery in your already-busy life.

If you haven't tried one of my workouts and aren't newly postpartum, check out this sample treadmill workout. This is for an intermediate/ advanced client. Do this only if you are feeling well and go at your own pace.

For those of you looking to build more strength, you have to sign up for the MamaShred Method Online program! This is my most effective workout for strength building, weight loss, and functional training. The MamaShred online program includes workouts for at home, the gym, pregnancy-friendly workouts, postpartum friendly workouts, bonus Pilates, and more.

I also have workouts for your period week, return-to-running programs, and more. Your workouts should fit into your life, not the other way around.

Reach out with questions. Don't fall for internet bs. You're too pretty for that.

xo SA

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