Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to do dips [title] Find an assisted pull-up/dip machine at the gym. [step] Most gyms with extensive weight sections will have this piece of equipment. It has a platform where you place your knees or feet and weights that can be adjusted to counterbalance your body weight.

Ending1: [substeps] Make sure that you can easily lift any heavy tool or weight on the machine. [title] Decide whether or not you are bringing your regular or stand-up pull-ups, spins, and dips. Ending2: [title] Ask for assistance from a gym employee or personal trainer the first time you use this machine. [step] If you are a first time weight lifter, assistance will reduce the likelihood of injury. Ending3: [substeps] Stations can be purchased at workshops around town or online. Pre-made dips come with a regulation wheel that can be opened and removed to be rotated. Ending4: When you sit in a squat position to do a dip, keep your shoulders back and keep your head elevated at all times while you do the dip. [substeps] An assisted pull-up that features platforms to support hands, feet and arms is ideal for infants under the age of five and 8 weeks old.

Answer format: ending1/ending2/ending3/ending4