i tried this one today, couldn't tell you how efficient it is since i haven't been doing it for a long period of time but it feels pretty good + it's only 10 minutes so you shouldn't have much trouble making time for it. ^_^ the channel has lots of other really great and decently timed workouts that you can combine with this one and do throughout the day.
some of the exercise things in the ab one are hard to do at first but you'll get used to it!!! good luck have fun xo
Kettlebell swings have changed my life lol. If I could only do one move, that would be it. Not only have they helped strengthen and tone my core, but my thighs and butt look so much better too. Ive weighed about 130 pretty much my whole life, but had a higher body fat percentage. I still weigh about 125, but I dropped 2 dress sizes and 14 total inches in about 3 months. I am more defined than Ive ever been, and I feel strong for the first time in my life. And the best part for me is that I only do a kettlebell routine for about 4 hours total each week, broken into segments sometimes as short as 15 mins.