Parkour: The aim of "free running" is to travel from A to B in an urban environment using a mix of running, jumping, balance work and climbing, all of which combine to build stamina, strength and flexibility.
Coasteering: Ultimate in all-round fitness: you have to navigate rocky coastlines at sea level, by way of rock climbing, scrambling, swimming and jumping. Builds strength and coordination; also burns lots of calories.
Parkour: It takes guts to execute a move for the first time - traceurs must overcome the fear of failure and injury. But with no rules or boundaries, the sky is the limit for those addicted to the adrenaline rush.
Coasteering: Thrill-seekers will certainly get a kick out of traversing a cliff overhang with foaming water swirling beneath, or plunging 20ft into the water when their climbing route reaches a dead end.
Parkour: A traceur needs strength and muscular endurance in the upper body for lifting and holding body weight, combined with lower-body power to execute jumps.
Coasteering: Swimming and climbing build strength and definition in the back, shoulders and arms - and increase upper-body and grip strength. But overall the extreme urban surfaces of parkour are more demanding.
Parkour: According to UK research, most accidents are caused by attempting difficult manoeuvres without adequate practice or protective equipment, and while training alone.
Coasteering: A rocky coastline and the unpredictability of the ocean present a potentially hazardous environment, but organised "coasteers" follow tried-and-tested routes that minimise risk.
Parkour: Builds kinaesthetic awareness and coordination, as well as honing reflexes and decision-making skills, in order to select and execute a move proficiently.
Coasteering: Involves choosing the best route, reading the conditions and making decisions about whether to swim, climb or jump. This improves problem solving and planning skills.