Well, leaving aside the problem of taking off (which today is improving thanks to electric motors), I guess one could say that gliders[1] are the closest we can

Well, leaving aside the problem of taking off (which today is improving thanks to electric motors), I guess one could say that gliders[1] are the closest we can have to human-powered flight and it's highly efficient in terms of energy consumption [1] https://en.wikipedia.org/wiki/Glider_(sailplane) https://en.wikipedia.org/wiki/Glider_(sailplane)