The 15-15-15 workout is so quick, you more or less break a sweat then you're done. At least that's what it feels like. This is the workout for anyone who'd rather do anything besides cardio exercise.
Evidence shows that pulling on your trainers for a run, heading out on the bike, or getting 10,000 steps in at home is the way to better health. Recent research even suggests that having good aerobic fitness, which comes from cardio exercise, is more important than BMI for longevity.
But, it's not everyone's favourite workout - so, the good news is you don't have to do it for long to reap the benefits. No one knows this better than A-lister Jennifer Aniston. In an interview with InStyle, the health-conscious star said she started following the 15-15-15 workout after an injury meant she could only do a Pilates workout and while she "absolutely love[s]" the exercise, she missed "that kind of sweat when you just go for it."
"I'm going back to my 15-15-15, which is a 15-minute spin, elliptical, run. And then just old school: I can chase myself around a gym," she said. Aniston also discovered the Pvolve workout around this time, before becoming an ambassador for the Pilates and weights-style workout brand.
Want to give the 15-15-15 workout a go for yourself? As woman&home's digital health editor and a fitness instructor, I've unpacked all you need to know about the workout with the help of a certified personal trainer.
15-15-15 workout: What is it?
As described by Jennifer Aniston, the 15-15-15 workout is a 15-minute spin, a 15-minute session on the elliptical (also known as the cross trainer), and a 15-minute run on the treadmill. Overall, the workout is 45 minutes long with exercises done back to back.
There are no time or distance goals to aim for, making it a great cardio exercise for beginners looking to improve their aerobic fitness, boost endurance, and potentially lose weight, given the calorie-burning potential of these exercises.
Sarah Campus, personal trainer, cardio and strength specialist, and founder of LDN MUMS FITNESS, suggests dividing the 15-minute sessions up like so: "Plan your intensity levels ahead of your workout. Begin at a steady state or moderate intensity, then onto the second 15 mins, look to maintain or increase intensity, and same with the third 15 mins, but use the final minute to cool down and stretch at the end," she says.
I tried the 15-15-15 workout
I tried the 15-15-15 workout six times over the past two weeks to see what it was all about. I don't mind cardio exercise - I enjoy running for 20 minutes a day and cycling in the summer, but I could see the benefits of this quick session.
My favourite thing about the workout was how quickly the time went. It's a very efficient workout. By the time you've built consistency and speed, you'll have less than 10 minutes to go as you only spend 15 minutes on each machine. 10 minutes is next to nothing with distractions like music or a podcast - and research from New York University shows that workouts seem less intense after 10 minutes anyway - so it's hardly surprising I found I wasn't fighting the same feelings of boredom as I do during a standard treadmill workout sometimes.
On busier days, I appreciated that I could break these intervals into even shorter ones. For example, on my second day of the 15-15-15, I wanted to do a resistance band leg workout so I added my 15 minutes of treadmill work as a warm-up and 15 minutes on the bike at the end, to cool down and stretch out my legs. I skipped the elliptical and took a brisk 20-minute walk outdoors to clear my mind after work.
As someone who's spent time away from exercise due to injury, I'm very wary of doing too much impact-heavy exercise - like spending more than half an hour on a treadmill. Monotony aside, it's tough on my joints. The exercise bike and elliptical offer a break from heavy exercise, while delivering an (almost) full-body workout.
While you're not doing endless cardio and you are getting more cardio into a routine, I couldn't see myself sticking to the routine in the long term. I would get bored doing it for more than a few weeks.
Shop Jennifer's fitness essentials
While I recommend doing Jennifer Aniston's 15-15-15 workout at the gym, you can do her other favourite - the Pvolve workout - at home. The Signature Kit includes everything you'll need to get started - including one month's worth of free access to the live video platform.
We loved Jennifer's charcoal grey workout leggings as an alternative to black activewear and this pair is in my top 3 health editor-recommended workout leggings. They have a secure waistband with a tie front for added security and handy pockets for storing your phone during your workout.
Jennifer Aniston's been spotted in her Oura Ring many times over the last few years. Much like one of the best fitness trackers, the smart ring records time spent exercising and the impact it can have on your body, time spent asleep and the quality of that sleep, alongside other health metrics.
Benefits of the 15-15-15 workout
1. Boost heart health
The 15-15-15 is designed to get more oxygen around the body, boosting cardiovascular fitness. Between the indoor bike, the treadmill, and the elliptical machine, almost every set of muscles in the body is covered - including the upper body and core - as well, making this a full-body workout.
The NHS recommends that every adult does 150 minutes of moderate-intensity exercise per week for cardiovascular health, with research from the likes of Ohio State University suggesting that exercise has a positive link to reducing the risk of cardiovascular disease and Type 2 diabetes.
That's 150 minutes of exercise at 50 to 60% of your maximum heart rate (220 minutes minus your age). If you follow the 15-15-15 workout, you'd only have to do it three times to meet the requirements for the week.
2. The 15-15-15 workout is time efficient
Being only 45 minutes long in total, the 15-15-15 workout is very time efficient. Campus agrees this is one of the main benefits of the workout. "It feels less like traditional cardio. It has more variety with shorter segments, making it feel dynamic and less like you're doing endless cardio, which can be boring and monotonous for some."
Plus, the fact it's time efficient means it's easy to stick to. "Consistency and sustainability are the most important thing and a varied and manageable routine is more likely to become a habit," she says.
3. The indoor bike and cross trainer are light on the joints
One of the most common complaints of cardio exercise is how it impacts joints in the knees, hips, and ankles. With the 15-15-15 workout, only one of the three exercises involves loading up the joints.
The indoor bike and cross trainer are light on the bones and joints, making them a good option for those who experience discomfort in this area, says Campus. "Women can lose up to 20% bone density as they go through menopause, so doing this lower impact workout gives women the benefits without putting their bodies through too much stress," she adds. "It can also support your mental health without risking impact injuries."
4. Versatile
While the traditional 15-15-15 workout involves doing the exercises back to back, there's no reason why you can't do these over the day. This is what's known as exercise snacking and it has some benefits for heart health, physical function, and mental health, per research linked to UNSW Sydney.
Also, as noted, you can swap out different cardio machines and exercises to suit your schedule and mood. For example, walking briskly for 15 minutes is just as good as 15 minutes of steady running on the treadmill.
"The 15-15-15 workout can boost endorphins without you feeling overwhelmed," says Campus. "You can still enjoy the mental health benefits of cardio, such as [improved energy], mood, and stress relief without feeling stuck in a repetitive activity."
Who should avoid doing the 15-15-15 workout?
If you want to build and maintain muscle through perimenopause and beyond, it's recommended that you do some form of strength training for women in your exercise routine - as well as the 15-15-15 workout. Also known as resistance training or weightlifting, this type of exercise challenges the muscles in a way that this cardio exercise won't do.
Learning how to do a push-up properly and how to do a squat correctly are two ways to build a simple upper and lower-body strength workout at home.
Also, if you're new to exercise or have any previously diagnosed health conditions, it's best to speak to your doctor before doing the 15-15-15 workout.
