As I continue to try and force myself to breathe through my nose, this evening’s Zwift session turned to ‘interval power play’ over a 10km distance, taking just over 30 minutes to complete.
The way I look at it, if I’m to commit to doing three sessions a week on the bike, then one of them should at least be of an interval variety, or higher intensity over a shorter period.
See the yellow, grey, yellow, grey peaks and troughs below? Those will be the intervals. And while my FTP sure as shit isn’t what it used to be, this one gets the heart going. Over the course of 30 minutes on the bike, my average HR tipped just shy of 140, peaking in the 160s. I’m also trying to manage that by strictly breathing through my nose when cycling but it’s proving to be a tough task.
So wait, what exactly is interval training?
For the uninitiated, interval training is basically like a workout with built-in bursts of speed. Imagine you’re running for exercise. Instead of just jogging at a steady pace the whole time, doing your 5k around the ring road of a Tuesday night, you would alternate between short periods of running faster and periods of recovery at a slower pace, like walking or jogging slowly. In my case, I’m spending a minute cycling above my FTP (Functional Threshold Power), and a minute at approximately half my FTP; in this case, one minute at 195w, one at 95w, ten times.
It’s not new territory to me by any means, but it’s taken a while to come back around to focusing in on interval training, even if it’s only going to be for one day a week for the moment.
If, like me most of the time, you can’t set aside an hour or two in the day to get some steady-state cardio in, then an interval session (or HIIT session) can help you work up a sweat and burn more calories in a shorter amount of time. Granted, you’d need to be calorie counting to do that, but think of it as expending more energy. Some people will also tell you that HIIT elevates your metabolic rate, helping you to keep that fire lit even after your workout is in the books.
Take this evening’s session for example. There’s the warm-up, five minutes of a slow build, getting the legs up to a steady pace but keeping the power output relatively low. Once the five minutes is done, it’s straight into the first interval, pushing hard for a minute, before shifting into the recovery interval and taking the pace right down for the next minute. Ten times fast, ten times slow. Your heart rate raises, then lowers. By the latter stages of the intervals, it might rise a little quicker, and take a little longer to come back down, but that’s the beauty of it. Once the intervals are done, it’s a five-minute cool-down period, and we’re done.
Do the math. Warm up (5 minutes), intervals (10 x 2 minutes = 20 minutes), cool down (5 minutes). That’s 30 minutes door to door. My temperature is up, the sweat is on, I’ve got a thirst on, my heart’s been up and down, and I’m feeling great.
Are there benefits to interval training?
I wouldn’t be doing it for the good of my health, except for the fact that I am actually doing it for the good of my health. Sure, there are benefits to interval training or HIIT (high-intensity interval training), as much as there are some downsides.
In the plus column, interval training as much as helping you burn more calories in less time (you’ve still got to graft), it can over time strengthen your heart and improve circulation, a win-win for your cardiovascular health. This can lead to a lower risk of heart disease, stroke or other chronic conditions.*
Another plus, once you’re in the swing of interval training, you’ll find that your endurance improves. Going for ten intervals to start with? Maybe you manage 12 or 15, or maybe the time on each becomes longer ‘on’ and shorter ‘off’. I found this a few months after taking up jiu-jitsu. The first few weeks of rolling were horrible, but like anything conditioned, you get used to it, improve your stamina, improve your endurance, the intervals helping to train your body to work more efficiently at higher intensities.
Having read Glucose Revolution last year and having spent some time looking at blood sugar levels and insulin sensitivity, interval training can help with both, beneficial for people with diabetes or prediabetes.
Plus it can keep everything interesting. The workouts are shorter and can be way more varied compared to a traditional cardio workout, helping to stave off boredom or complacency. And look, as I said, there are the downsides. High intensity can be tough and demanding on the body, requiring you to push yourself to near-maximal effort during the intervals, not easy if it’s your first rodeo. Unless your form is right and your head is in the game, there could be an increased risk of injury, and if not through injury, you’ll need more rest between HIIT sessions compared to lower-intensity exercise for optimal recovery. As much as they can be physically demanding, a solid interval session can also be mentally demanding and challenging, needing a lot of focus and motivation to push yourself through the workout, especially in the closing stages.
But did I have fun? Yes.
Will I do it again? Yes.
Will I be writing as much about it next week? Probably not, but that’s ok too.
*Note: I am no doctor. Nothing I offer or suggest here should be taken as medical advice and you should always consult your GP before engaging in physical activity if you have concerns over its impact on your health.
