Fartlek (Swedish for Speed Play) Descending Tempo Fartlek Begin this session with a 6:00 minute run at roughly your half-marathon pace (if you don’t know what your pace would be just aim to be slower than usual) The recovery is half of the time of the piece (in this case 3:00 minutes) Run for 5:00 minutes slightly quicker than the 6:00 (with the rest now being 2:30) Run for 4:00 piece a touch quicker (2:00 rest), 3:00 run (with 1:30 recovery), 2:00 run (1:00 recovery) Finish with a 1:00 run. The final two pieces of this fartlek should be working into the current 5K fitness range. 31 minutes. From UK Active

Steady runs are a great way to build aerobic strength, which is the foundation for your best performances from 5k, 10k, half to full marathon.
Steady runs should be “comfortably hard”, which is perfect when the objective is to add a little bit of hard running to the schedule, but not go overboard.
Start each steady run with a mile at normal, easy pace. Keep the pace easy, this mile is a warm-up mile to get the blood flowing to the legs and loosen up your muscles.
After the first easy mile, take a brief minute or two to stretch anything that is tight, sore, or that has been bothering you lately. I like this dynamic warm up sequence to prepare the body.
Ease into the steady pace over the first mile or two.
You don’t have to go from standing start to steady pace in the first 100 meters. Let your body fall into the pace naturally. Some days this will feel easy and other days getting down to steady pace will be a challenge.
Because steady runs are usually a little longer than tempo runs, you’ll have to work on concentrating over a longer distance. Work on staying focused throughout the run and concentrating on your pace and effort.
Use the last mile as a mini cool down. Bring the pace back down to an easy pace and enjoy the feeling of job well done. The cool down will help your muscles relax and start the recovery process.
Enjoy your Run
Sue and Debbie