5,000 - 10,000 Meter Training
Training for the 5k or 10k is similar with a slight difference in such that weekly mileage may be a little higher if you are training for longer distances, but not by very much. The difference in mileage should simply come in the form of additional runs (add a morning or evening run to your weekly training and get some double runs in) or maybe longer recovery runs. But again, you do not need to stress much more mileage here. Instead, I believe it's more important to focus on focusing and being aware for a longer time than it is to actually run more mileage. The hardest part of racing a long distance event, in my opinion, is to mentally stay alert without "falling asleep" during your race. Spend time during training runs actually focusing mentally on what you are doing - pace, form, technique. Use recovery days as a chance to train yourself mentally to be aware of your breathing and technical work while you are running. The person that wins a long distance race is the person that decelerates the slowest. The person that can stay out of oxygen debt and delay the build up of lactic acid will win the race. Pay attention to what you are doing, stay relaxed and control your breathing.
If you are training to compete competitively in a race of these distances, I recommend running 50-70 miles per week. Keep in mind that this is a big difference and that there are factors that go into figuring out which range of mileage is right for you.
1) What level of fitness and experience are you at?
If you are at a strong fitness base and on a collegiate team focusing on the 5k/10k, 60-mile weeks should be about right for you. If it's early in the season, alternating 60-70 mile weeks can be beneficial so that you can run 60-miles on weeks where you have a race and 70 during weeks where you are not competing. By the time you are getting closer to championship season, you want to reduce the amount of miles you are running per week.
2) What type of terrain are you training on? A track? roads? grass and trails?
If you have access to soft surfaces like dirt trails and grass, do what you can to get most of your miles on that type of terrain. Try to run your workouts on the same type of terrain that you will be racing on. However, try to avoid running a lot of mileage on pavement, it is not good for your shins and knees. If you are limited to running on roads, then I strongly recommend keeping your weekly mileage on the lower end (closer to 40 than 70).
3) How much time do you have to prepare for the race? Do you have months to train? Weeks?
When I design training programs for long distance runners, I count backwards 24 weeks from the day that the race that we are preparing for is on. I'll get into more specifics regarding this in a post dedicated to focusing on training calendars, but after figuring out the 24 weeks between the race and the starting date of training, I then divide that 24-week segment into 4 periods of 6-week training plans. The first 6-week segment being base building and easy running. The next 6-week period focusing on increasing mileage and beginning workouts. The following 6-week segment has race specific workouts and some races mixed into the training to help get ready for the main race. The last 6-week period is to start the "peaking" process in which rest and recovery is a major focus with lower mileage weeks.
The following are a few workouts that I utilize when preparing runners for the 5k-10k. A rule of thumb that I use is to have the total amount of distance run during a workout (not counting recovery jogs in bewteen sets) not go much higher than the distance that is being trained for (i.e. if you are training for a 5k - you would run 5 x 1000-meters, whereas if you were training for a 8k you would run 8 x 1000-meters).
5-8 x 1000 (500-meters or 3:00 jog recovery after each interval)
5-6 x 1200 (600m or 3:00 jog recovery after each interval)
3-5 x Mile repeats (800m recovery/3-5:00recovery inbetween each)
3-5 x 2k repeats (jog 1k for recovery after each)
2-3 x 3k repeats (1200m-1-mile jog recovery inbetween)
3 sets of 5 x 500 (100m jog recovery during set/400m inbetween sets)
12-20 x 400 (100-400m jog recovery depending on your fitness level)
3-6 miles of Fartlek followed by repeats of 150-400 meters
The goal pace for each workout should be your race pace for the event that you are training for with the exception being the 150-400 meters that are after the fartlek run. Those should be fast and used as speed work.
When it's all said and done, don't overthink or stress out. Believe in yourself, have faith in your training, have fun and you will do fine.