Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to work out longer [title] Set a goal. [step] Before you aim to increase the duration of your workout, you have to know what your end goal is and how you will get there. Set a goal that is: specific, measurable, attainable, realistic, and timely.

Ending1: [substeps] For example, set a goal to add two extra minutes to your workout, five days a week. Once that's attained, you can revisit your goal and opt for five extra minutes five days a week. Ending2: Don't set an unrealistic goal, or else your body will feel like you're saying no to the goal. Setting an achievable goal doesn't have to be a big challenge, but the goal you set should be realistic and achievable. Ending3: Strive to lose five pounds per week so that you don't feel overly drained or stressed. [substeps] Your goal should be vague, time-stamped, and achievable; you don't want to write it down all over the desk just in case you catch up with it later in the day. Ending4: [substeps] Tell yourself that you will do a moderately intense workout with one set of exercises per week. Say that you will do at least three sets of three days a week, each time starting your workouts in the morning and moving back at lunch.

Answer format: ending1/ending2/ending3/ending4