timing how long it takes for your kettle to boil 1 cup (250ml) of water. looking at the power of your kettle (Watts, often found on the base of the kettle) joules = wattage x time (in seconds)
Rock climbing can help build and tone your legs and glutes. Indoor rock climbing is a sport that when properly executed, recruits every major muscle group in the body. Rock climbing is a full body workout that tones and strengthens the arms, shoulders and core muscles. You can also effectively strengthen and tone your legs and buttocks with regular indoor rock climbing sessions.
The trick to keeping your legs straight in cartwheel, or in any other exercise, is the contraction of the quadricep. So, in order to extend the knee, you have to contract the quadricep. So, whenever you need your leg straight and to keep your leg straight in cartwheel, think quadricep and full extension of the leg.