It's true what others say- don't attempt this hike if you're not fit and you don't have proper footwear. That being said, it's 4 hours of hiking and it is a really great hike. The rainforest is beautiful, we got to see a monkey and our guide David from Poinciana Tours was awesome.
This is a great activity to do on the island if you're sick of sitting at the beach all day. I wouldn't attempt it on your own- the trails are not well marked and it would be pretty easy to get lost.