I Tried a 12 Week HIIT Workout Challenge… This is What Happened

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Today I’m sharing with you a really intimate post… my HIIT workout results, including my HIIT workout before and after pictures.

I’ve read articles about people who did Yoga everyday, did a plank everyday, gave up alcohol for a month, or did 10 minutes of strength training everyday, I once tried Intermittent Fasting for a month, and I tried running four times a week for 3 months, so I was curious what doing a HIIT Challenge could do for me. 

If you’re looking to try Intermittent Fasting, check out my post and my Intermittent Fasting results here, and check out this post if you’re interested in what happened when I worked out with a virtual personal trainer.

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Rear view of a blonde woman with her hair in a pony tail wearing a black sports bra and black capris with her hands on her hips with caption: I tried a 12 week HIIT Challenge... This is What Happened".

My HIIT success story

My mom passed away in January after a 4 month battle with cancer. She lived 5km from my house, so I was very close to her. When she was diagnosed I went to my parents house and helped my dad out most nights with mom’s care as the cancer had made her bedridden, and the pain medications impaired her thinking. My dad needed lots of help.

I took a week off of work after she passed to help me grieve. We were in a lockdown, and there was nowhere to go and it was a cold miserable January. While I only run outside, and I’ve been running for over 20 years, I just couldn’t motivate myself to do it – the thought of running in the cold made me miserable, and all I wanted was to feel better.

During the days my husband was working from home in his office, and each of the kids were in their rooms attending school online, so I was trapped in my room, grieving with nothing to do. I decided to find a workout video on YouTube. I had purchased a set of dumbbells for my daughter’s weightlifting class she was taking online, so I decided that since I had invested so much in them, I should use them.

HIIT workout review

The first video I found was a no repeats HIIT video of Heather Robertson’s and I fell in love! It was amazing and exactly the level of difficulty I was looking for! I got the endorphin rush I LOVE and it was not like anything I had ever tried before. I discovered that the workout was part of a 12 week program, so I thought why not give it a try?

I loved that it’s completely free and on YouTube. I loved that I could do it in the comfort of my bedroom and I loved the variety of the workout program. Some days focused on full body, others on upper body or lower body and then, there were no-repeat days (my favourite!). The programme has a lot of High Intensity Interval Training (HIIT) exercises incorporated and I find these to be super effective when it comes to burning fat and improving my fitness.

What is HIIT?

HIIT stands for High Intensity Interval Training. HIIT workouts generally combine short bursts of intense exercise with periods of rest or lower-intensity exercise, these workouts often mix aerobic and resistance training. These can be 20 seconds of work, followed by 10 seconds of rest, or they can be as long as 45 seconds of work with 15 seconds of rest.

What HIIT Workout Challenge did I do?

I found Heather Robertson’s 12 week Challenge on YouTube, then I found her Facebook group. After asking a few questions in there, I was encouraged to try both the 12 week challenge and the monthly workout calendar (the monthly calendar is a pdf calendar emailed by Heather every month outlining workouts to do from her collection of YouTube workout videos). While I was heavier than I’ve ever been when I started, I’ve been very active over the past 20 years so I knew this runner needed a BIG challenge.

On February 4th I started the challenge and I finished the HIIT challenge on April 25th.


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My starting point

I’m a runner, and while I did continue to run 4x/week most of last year, and did HIIT workouts two mornings/week outside with my neighbour, the stress of the year had taken its toll on me. One of the last things my mom said to me when she and I were at one of her oncology appointments was: “When are you due?” She was excited that I was going to have another baby – I wasn’t expecting though, stress (and mostly overeating) had caused me to be the heaviest I’ve ever been despite exercising regularly.

At 45 years old and 5 feet 2 inches, I started this challenge weighing 143.6 lbs, with a BMI of 26.4, a body fat % of 31.5%, a resting heart rate of 69 bpm, and VO2 max of 36.9.

Related: If you’re looking for how to lose weight by fasting, then check out my Ultimate Guide to Fasting for Weight Loss.

12 Week HIIT Transformation Before Photos

The first thing that happened

The first thing I noticed was that unlike running, I wasn’t crazy hungry after working out. After getting dressed, out the door to run, running for 5km (which takes me at least 30 min), then coming back home, getting undressed etc. I always felt like I deserved a big ol’ snack. I love cooking (after all this is a recipe blog), so I often have some delicious baked treats around, that I felt like I deserved after going for a run. I probably eat back all of the calories I burned running within a half an hour of getting home. With the HIIT workouts I didn’t feel the same hunger, nor the same sense of OMG I did this amazing workout so I get to eat this Copycat Starbucks Lemon Loaf.

My one month HIIT results

After 1 month of doing HIIT workouts I started seeing some results. I only lost 3lbs but saw a huge improvement in my posture. The posture improvement made me look like I had lost 10lbs – it’s amazing the affect posture has on how we look.

My 6 week high intensity interval training workout results

Halfway through this challenge I was ready to quit. The workouts were fun, and while giving myself a “Star” on the printable tracker was motivating, I wasn’t losing weight nearly as fast as I wanted to. After 6 weeks of high intensity interval training workouts I had only lost 4lbs. My husband reminded me that was 3 lbs less than I was 6 weeks before, and half a pound per week over a year would result in a 25 lb weight loss, so I used that as motivation to keep going. The progress pics that I was taking were also starting to show a bit of a change.

My HIIT workout results

During Heather Robertson’s 12 week challenge I lost a total of 6.4 lbs and 1.9% body fat. The biggest change was not my weight, it was my posture! Both my posture and my self confidence improved so much!!

My resting heart rate also improved from 69 bpm to 62 bpm, and my VO2 max also increased! Not only did I look stronger, but I also had quantifiable fitness results!

My HIIT workout before and after transformation photos

I’m sure this is what you’re here to really see, and I don’t really blame you! Before I decided to invest the many hours into doing this challenge I searched out HIIT Before and After photos too!

IMG 3806 - Today I’m sharing with you a really intimate post… my HIIT results, including my HIIT before and after pictures.

As you can clearly see, the biggest transformation was my posture. My core certainly got a lot stronger – which I really hope will help me with my low back pain.


Focusing on the challenge helped me through the longest, darkest three months of my life. Instead of coming out of these lockdowns, and the grief of losing my mother even more overweight, I’m coming out in better shape than I was going in. I’m not sure what challenges I’m taking on next, but I assure you I’m not done yet!

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  1. Thank you for being so real and for sharing your story ! You rock 😍

    1. Janice - Salads for Lunch says:

      Thanks Ella!! I’m doing Heather’s 12 week 3.0 now and I’m really enjoying that one too!

  2. Thanks for sharing your results! I think it’s great that you focused on other aspects of fitness and not just the scale. Body fat and RHR are so important in the over all picture. Feeling stronger and having better posture are a win for sure. Most importantly sounds like you found something you like and will continue to do. Congrats on your success