Qualifying exigency leave, like leave for a serious health condition, is a FMLA-qualifying reason for which an eligible employee may use his or her entitlement for up to 12 workweeks of FMLA leave each year.
Considerations. You can change your calorie intake during training if you feel it is necessary. If you're gaining weight, try eating 200 calories less per day. Likewise, if your training is suffering and you lack energy, you're probably not eating enough, so add in an extra 200 calories each day.
Pick a plan. Twelve weeks is a common length of many half marathon training plans, but a quick Google search will bring up plans that range from 10 to 16 weeks. I prefer to use a longer plan (14 weeks) with my runners. The extra weeks allow for a little wiggle room if a runner gets sick or has slight setback or injury.