Since launching SmartCoach - our free, personalised training service - we've been inundated with questions about the science and wisdom behind the custom-made schedules it designs.

And who better to answer your queries than SmartCoach creator, and RW USA Executive Editor, Amby Burfoot? Here we've extracted your most frequently asked questions - along with Amby's answers - from his interactive forum discussion to bring you an insightful glimpse of how the schedules are designed.

A SC is 16 weeks because we had to pick some number, and that's the one we came up with. I actually like shorter programmes better than longer programmes. I think a lot of runners "go over the top" towards the end of their schedules.

Longer is theoretically better of course, but you have to be more careful. I say, if you're building up for more than 12 to 16 weeks, you'd better be very careful that you have period rest days and weeks in your programme.

Q SC gives me a pace for every run, why not for race day?

A We took a crack at that, but haven't incorporated it into the "live" code yet. Why? Because SC gave people relatively modest improvements and we were afraid that if we showed people these, they’d work backwards and pick a newer/faster program that will actually be detrimental to their training. Any coach can give you a programme that will kill you. The tough thing is providing a programme that you can achieve successfully, and that will also lead to consistent improvement. That's SC's goal.

Q How do I work out, from the training times, a realistic race day pace? Presumably my fitness will increase if I stick to the plan? - Dlb

A In your first races, you should simply aim to start at what feels like a comfortable pace. You'll probably go out too fast anyway, so the more you hold yourself back, the better. In the first mile, you need to keep saying, "Take it easy. Take it easy. Take it easy." After a mile or so, your body will tell you what to do. But don't force it. Stay as relaxed as possible. You should be running hard-but-controlled. You shouldn't feel massively out of breath.

The only way to learn racing is to race. And you'll learn quickly. Everyone does. The good news is, after a race or two, you'll be able to refine your SC training plans to get them exactly on target for your fitness.

Q A lot of other training schedules have a speedwork session every week but SC doesn't tend to do this. Do you think for longer distances (10 mile, half-marathon) you need to do speedwork every week or is it better to do tempo runs some weeks and speedwork every two or three weeks? - Bluesocks

A This is one of those areas where SC, being just a computer program, can't make individual adjustments. It's possible that you or someone else might respond well to more reps. At some point, every runner has to figure out what kind of training he or she enjoys the most, and gets the most benefit from.

In general, SC and I don't believe you need a lot of reps for the half-marathon and marathon unless you are an elite runner. Non-elites mostly have to figure out how to get more efficient, have more endurance, etc.

Q Does SC limit long runs as a percentage of total weekly miles and does it limit weekly mileage increase? Also the easy and tempo paces improve with each four-week cycle but how do you decide by how much? Finally the schedule SC has turned out for a half-marathon (25-30 miles a week, very hard) has a longest run of 13 miles. Do you think that is enough? - M.

A SC does all the things you're implying. The mileage and paces increase on a consistent, graduated basis. This is the "collective wisdom" part of SC. SC also eases you back once a month to make sure you are recovering properly.

I see no reason to go over 13 miles when training for a half-marathon. I know plenty of coaches who don't think you need to go longer than 8 or 10 if the half is your goal. Obviously you will need more if you are building up to a marathon. Finally, as your race distances get shorter, training pace becomes more important than distance.

Q I am aiming to cut my next half-marathon time by 25 per cent - from 2:00 down to 1:40. Are the schedules tailored for this? - Tanya Watson 3

A I'm not sure your goal is very realistic. It could be, but only if you did little training for your first half, and if you have lots of talent. SmartCoach (SC) would never claim to enable you to make that kind of gain. SC is programmed to be conservative, help you improve, but very importantly to keep you from overdoing it and getting injured. SC believes in gradual, successive improvements. A good goal, still challenging in fact, would be a five per cent improvement.

A Sure, adjust SC or any other program to whatever suits you best. SC has options for people who can't run many days a week, but you can also change an easy run day to cross training if that works best for you. Here's a thought: The smartest SC user will be the one who takes the parts of SC he likes, and makes adjustments on the other parts. As long as you don't start over-training.

With regard to weight and marathon running, there's no doubt that it's an advantage to be smaller and lighter. Just look at the Kenyans and Ethiopians and Japanese. But Paula's not short, and some big, strong runners are very fast. Again, the only thing any of us can do is to be the best we can be, and make the sport work for us - keep us healthy and fit. That might bring a gold medal to some. But for most of us, it's about personal challenge, satisfaction, and good health.