It would depend on your height and frame. I've added a link below to help you work out what is healthy for you.
Twenty is a score so twenty years is a score of years.
Twenty Years After was created in 1845.
Joseph was either in prison for twenty years or in Egypt for twenty years. But I think it was Joseph in Egypt for twenty years.
Twenty Years of Dirt was created in 1986.
Twenty One Years was created in 2006.
Twenty Good Years was created in 2006.
The Twenty Years' Crisis was created in 1939.
Musketeers Twenty Years After was created in 1992.
That is the correct spelling of the period of "twenty-seven years" (27 years).
Twenty years old is はたち
The word for every twenty years is "score."
The duration of Twenty Good Years is 1440.0 seconds.