A study recently came out from the Norwegian University of Science and Technology concluding that,
The main finding from the present study was that a single bout of exercise that consisted of 1×4 min at 90% HRmax (1-AIT) increased VO2max to a similar extent as 4×4 min at 90% HRmax(4-AIT), when both protocols were performed 3×/wk for 10 wk in healthy overweight middle-aged men. Both interventions also induced similar improvements in submaximal work economy, blood pressure and fasting plasma glucose, but 4-AIT was more effective in reducing blood cholesterol and body fat.
The full article can be found here
And now there are a load of articles all over the net that take these results and say, “yay, we only need 12 minutes of exercise per week to be in shape”. Don’t get me wrong – I’m a fan of the “Get in, get out” workout that takes as little time as possible, and I’m also a huge fan of high intensity intervals that increase VO2max. But 12 minutes of exercise per week is not going to get you where you want to be.
Where you want to be is in a happy place that requires a bit more effort. I’m not suggesting doing Crossfit 5 days per week, but if you’re going to get up and do air squats or whatever for 4 minutes 3 days per week, throw in another 10 to 15 minutes each workout and do some pushups, situps, add some pull-ups or if you got weights around, lift them. Seriously. Even Crossfitters who brag how the Fran workout only took 4 minutes to complete, will be seen hanging around the gym for another hour, practicing double unders and working on muscle-ups.
Yes, maybe you can lose weight doing 4 minutes of working out 3 times per week over 10 weeks. Yes, maybe you decrease health risk factors and decrease the chance of heart disease and stroke. That’s awesome. But maybe you also want to build some muscle and get actually stronger. All the VO2max in the world won’t help you lift furniture.
So let me be the first to say, with the caveat that this is just my opinion, 12 minutes of exercise is a great start, but it aint good enough.