Today I was scheduled to run 6 miles with a few efforts of speed work tucked into the warm up and cool down. I worked 12 hours, seated at my desk, and my hamstrings were getting a little tight so I decided that taking a day off wouldn't be the end of my training.
Even though I've been training for years, I still feel strange about skipping workouts. For the longest time I really didn't know how to recalibrate my training to accommodate for the missed workouts.
Some coaches said don't let it change your training plan, just keep going on to the next workout. I guess that would work if you only missed an easy workout. However, skipping specific training runs like tempo, speed, etc. can impact the periodized training plan, especially if you skip a couple of workouts in one week, or the whole week all together!
Things like doubling up your next workout with extra distance or speed are good ways to get injured. The fact that you're competitive, in shape, and could hammer a good workout, doesn't mean you should.
These days, I just take my skipped workouts "in stride" and finish out the week with whatever is left over. If I am training for a specific race, I'll just adjust my training with a couple of tweaks that will get me back on track the following week. Because periodized training is so important you don't want to completely de-rail your plan. Knowing that missing a series of workouts could set you back a week or more is a good motivator to stick to the plan.
So, I skipped yesterday and I'm thinking I'll put in a couple of miles tomorrow and a few more on Saturday and then get back on track starting Monday. No stress. No worries. No need to freak out. Just run and get over it.