Lots of people use a foam roller, either before after exercise. It's not usually a very comfortable experience - as Greg finds out in this episode - but is worth the pain? Can they really increase flexibility before exercise, and ease our muscles afterwards? Is it any better than stretching? As you'd expect, there are plenty of claims around these products, which cost anything from a tenner to more than £100 for a vibrating version. We're going right around the world for this one - listener Brendon joins us all the way from New Zealand, and to get him some answers we've got foam roller expert Dr David Behm dialling in from Canada. National Physiotherapy Lead for Nuffield Health Jodie Breach also joins Greg in the studio. So are foam rollers the best thing since sliced bread? PRESENTER: GREG FOOT PRODUCER: TOM MOSELEY