Ready to run

For starting slowly - go for a 2-2.5 mile run/jog. I know it seems a short distance but increase by a half mile each week; you'll get back to 7 miles or so sooner than you think!

Do you have a Swiss ball at home? If not I'd suggest buying one - they are cheap and a great addition to your core routine. What most people I find don't understand is that 'core' isn't just your abs! It's your abs, obliques, trunk in general as well as your back!

Assuming you either have or are looking into a Swiss ball, do back extensions on it. A sore back can mean weak muscles in that area; could also mean you don't have proper form. I've been correcting plenty of people doing things wrong at the gym to help with injury prevention - and I'm visually impaired so thee fact I can see those mistakes right there says A LOT about form.

For your core if you don't want to do sit-ups or even crunches go for leg raises. They work your core and find they help with back soreness. Other exercises would be windshield wipers/pendulums, full and side planks, v-sits, trunk rotations and that sort of thing. For your breathing economy as well as core work there are running planks you could do as well as an exercise which I forget the name.

For running planks, get into 'up' position (as though you were about to do a push-up) and using your core as well as hips just a bit, lift the opposite leg up and aim it towards your elbow.

So as an example I'm in up position and I want to start with my left elbow, using my core muscles mostly I'll lift my right leg up and aim the knee towards the elbow without letting them touch and go back to the original position and then do the same with my left knee/right elbow. You want to do these quickly - it's almost like running stationary feels like. Aim for about 30 seconds of this.

The other is as follows: lie on your back and lift your legs as though you were getting ready to do Russian twists. So a slight bend in the knees, feet off the ground at all times. Using your core lift your upper body off the ground and move your arms at a good speed like you would when you run. So shoulders and hands relaxed, fingers lightly touching if you like pretend you're holding a potato chip in each hand but don't want to break it. Do this for 30 seconds or however long you can to start. Looks weird but this exercise works your core and helps to open up your chest to help you breathe better during your runs.

When you run pretend you're a puppet on strings, so your back straight, eyes looking straight in front of you and run lightly on your feet and take short, quick strides. make sure you breathe in deep enough but not too deep and incorporate your nose and mouth in your breathing technique. You don't want too little air but you don't want too much either; just enough to fuel your muscles, and for things to be comfortable but you don't want to breathe in too much air which I've seen some people do so and it affected their form.