There's no magic number for how long your workout should go for muscle and strength gains. Here are the factors that play into how long you should work out.

What is a Tabata workout? In a traditional Tabata workout, you will perform an exercise at max intensity for 20 seconds and then rest for 10 seconds. This repeats 8 times for a total of four minutes.

Opt for light- or moderate-intensity activities, such as yoga or brisk walking. Limits the availability of workout classes: The morning may offer more access to group workouts.

For the regular person, a 4-minute Tabata workout is usually repeated up to 5 times, for a full workout that's 20 minutes long — which is still pretty short, just not 4-minutes-short.

I dropped down in weight to manage the high reps with speed, using a 15kg/ 33 lb kettlebell, and just completed the workout in 10 minutes on my best day and 11 minutes on my slowest.