Have had the half bike for about 2-3 months. It take sometime to manouver especially when it comes to turns. However after a few hours of practice you can start riding without falling all the time. Whne riding it you feel you leg, back and shoulder girdle muscles engaged so yes all your body is being worked up, and on top of that it involves balancing and co-ordination. My only issue is were i live there isn`t much flat spaces to ride - i have a lot of slopes and hills, i am pretty sure that with time one can gain muscle strength to go up most hills, but this will take time. I bought the half bike since i wanted an alternative to jogging after i suffered a prolapse disc. I wanted to avoid impact on my back and the half bike fits in nicely, it works the back muscles without putting to much compressive straing on my spine, hips and knees. I wonder if future version will have braking in the posterior wheels, if at all possible, this would add better control and braking
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