Hi, I initially started my half training with intent to finish and get friend coming off injury across finish line. Unfortunately she is sidelined again and competitive me has 4 weeks till race. Been getting all long runs in but very tired and out of breath by end of them. Previous PB is 2:01 last fall. I have 4 weeks till race. Would it be better to do hills till then or get on the track for some speed work? My training program says speed but I didn't do the hill workouts. Thanks!
Doing hills and sprints for the next 2 weeks will make some difference, but I can't say how much of course. Leave some good recovery time after the tough workouts and only do the hills or sprints 2 or 3 times a week at the most. You might recover faster than I do but overdoing it this close is not a good idea. Done right, hill intervals or repeats will give a dramatic improvement in a short time frame. My last half training session used 1 day of hill repeats per week over 6 weeks, and I ended up taking 10 minutes off that course from the previous year. If everything else is in place there's no reason not to go hard for 2 weeks.
Leave the last 2 weeks to just do easy work and be fully rested for the big race. That will probably have more of an impact on your final time anyway. Good luck on breaking 2 hours and let us know how it goes for you.
I'm a big proponent of the value of hill repeats. If you're running a hilly course they can really help. But with only 4 weeks to go they won't make a huge difference. And I wouldn't recommend doing them more than once a week. You could, however, do hill repeats one day and intervals a couple days later in the same week. But again, while they will help some, you're too late in your training to get a big boost from them. When you're doing them (either one), work on form, leg drive and turnover. Just be careful not to push too hard. You don't want to get injured.
As for the long runs, if you're finishing "very tired and out of breath", you are probably doing them too fast. They should be done at a fairly comfortable pace.
I think you are too late or too close to the race for either type of exercise to have any value.
The worse thing that could happen is that you add this new element into your training and you injure yourself, with little or no time to heal prior to your event.
I'd suggest do some shorter mileage runs over the next 3 weeks --- try to run them at your 5K pace. This will increase your cardio a little, give you some confidence, and will not risk the stress to the body of introducing speed work on the hills or track.