LifeFitness, the sports equipment company, has recently added a very cool function to their treadmills, cross trainers and bikes. Using their new app or their web interface, you can design your own interval workouts and load them into the LifeFitness devices using a USB stick.
On the LifeFitness Connect site: https://www.lfconnect.com/web/ you can build custom interval workouts stage by stage, creating each step in the workout by specifying the speed, length and even the incline of each interval segment. You then using the LF Connect USB desktop app for windows or iOS app, available at https://www.lfconnect.com/web/#uploadresult:upload . Then, after transferring your workouts over to the USB stick, you just insert the stick into the fitness equipment and start your workout. For instance, here are the first ten steps in my 45 minute interval workout (the entire workout had 34 steps, increasing to a 30 second interval at 15.3 km.hr):
I started off with five minutes of warmup at 9 km/hr, increasing to 9.3 km/hr for the next three minutes and building to 9.7 for an additional three minutes before backing off for 30 seconds at 8.9 and then starting the first interval of 12.1 km/hr for one minute.
The treadmill, like magic, automatically adjusts the speed for a given time based on how the intervals have been set up through the web interface in advance. Here is the entire workout today.. 45 minutes of intervals:
This is a great way to spice up a normally dreary treadmill workout, without having to mess with the speed buttons every time you want to increase or decrease your pace. This sort of periodic stressing of your system during a workout is the fastest way to increase your mitochondrial density and get in really good shape.