At 55 years old, I have found that my hands were going numb/tingling from leaning over too far on my 29" full suspension MTB. I installed a new adjustable stem that seemes to help by moving the handlebars upward, and closer to my body.
https://www.amazon.com/Adjustable-Stem-130mm-25-4-threadless/dp/B0026A1FKQ