I have recently been increasing my workout efforts substantially since I turned a corner for the better a couple weeks ago post-surgery. At 13 weeks I had significantly less pain and it seems as though I overcame a “hump” which allowed me to push harder than before in workouts.
Since then, I have been trying to rebuild my fitness that I have lost after a year of winding down the training due to injury. I am trying to do at least one workout a week on the trainer where I focus on sweet spot training. Since doing a few of these workouts, I have noticed a huge boost in my fitness on the bike as well as in the pool.
What is sweet spot training?
This is a workout where you ride in the zone that is roughly 85-95% of your FTP (functional threshold power). This website has a clear description of how to obtain your FTP. The sweet spot is meant to be an effort where you can reap many physiological benefits of training and increase your FTP over time without causing too much stress on the body that would require a longer recovery.
What does FTP actually mean?
FTP refers to the power you can sustain at lactate threshold.
Lactate threshold is the point where your body begins accumulating lactate in the blood, and can no longer rely on purely oxygen.
This works out to be the maximum power you can sustain over about an hour of cycling.
This power number in Watts can be thought of as a measure of your ability to perform as a cyclist. If you divide this by your weight, you will obtain your Power to weight ratio, which is a better indicator of your abilities as a cyclist.
Why does increasing FTP actually matter?
You may have brushed it off, thinking that if you just train harder, you will get faster. So why do we need to care about FTP?
The key here is that FTP allows you to train in your “sweet spot” so that you can actually improve. Performing intervals just below your FTP can be highly effective for improving your overall endurance and performance without causing excessive stress to the body.
You can tailor your workouts to your fitness level so that you aren’t working too far over or under your abilities and you maximize your ability to improve without needing prolonged recovery.
Sweet Spot Training with Zwift
I have tried doing the SST (sweet spot training) workout in Zwift, which brings you through two sets of “over-unders” where you ride at the top end of your sweet spot range for 5 minutes and then the low end for 5 minutes and repeat for a number of reps. I used to love doing these workouts when I was a spin leader. These workouts are meant to be difficult, but a good way to boost base fitness efficiently. These workouts are therefore ideal for the time-crunched athlete who wants to see improvements. Zwift has a short and long version of this workout, which is nice depending on the challenge you want.
The key before doing these workouts is to actually test your FTP. I am currently using my old FTP from 2 years ago as a benchmark, which was around 198W (you can set your FTP level in Zwift by dragging the cursor up and down on the workout chart before you hit go). The test takes 20 minutes where you ride hard, obtain your average power over the 20 minutes, and then take about 95% of that number. This assumes that you could hold 95% of that number for an hour, as your actual FTP is the power you can sustain for one hour.
Unfortunately, I think I was more fit 2 years ago, so the sweet spot workouts have been pretty tough for me. I am hoping to re-test my FTP next week so that I can have a more accurate indicator of where my fitness is currently. I think I have been stalling on doing this test because I know that I won’t be as fit as I would like. But, having said that, I am grateful that I am even able to do an FTP test given the set-backs of the past year! I have come a long way, and hopefully it will only be up from here.
Riding inside is not ideal, especially with recent California sunshine, but there are still a couple more weeks until I can ride outside (due to risk of breaking the hip in a fall). I do think that these structured workouts help a lot to stay focused and motivated during trainer sessions. The feedback is great, and although it can be harsh, you get an accurate sense of where your fitness stands. I will continue using these workouts for the upcoming months in the hopes of improving my FTP. Hopefully, they will benefit you too!