To cross the finish line of a 5k run in under 30 minutes is no mean task.

But it's one that is made much easier when you know some inside rules, or you follow a step by step, proven formula for success.

And now you're about to find out about step four.

If you've missed the last few weeks and have stumbled across this column, but quite fancy the idea of a weekly 30-minute fitness blast in your local park with a group of like-minded others, then these are the tips and hints you need to follow to do it much faster than you think is possible.

Week 1: Dig out the right reflective and warm clothing and make sure you're wearing sensible footwear. Begin one week of 'run a lamp post, walk a lamp post' routine for 30 minutes per night.

Week 2: Begin 25-30 minutes of CV work by mixing walking and jogging. Something more sustained like 30 second walk, 30 second run will suffice.

Week 3: For five nights out of the next seven, run half pace for just three minutes, walk three minutes and repeat four or five times as appropriate.

And if you've been following my system for fitness success these last few weeks and are ready to take the next step, here's the schedule you need for week 4:

Today: Run half pace for seven minutes, walk three minutes, repeat three times.

Sunday: Run half pace for three minutes, (depending upon how out of breath you are) - repeat four times.

Monday: At home in the warmth, seven to eight minutes jogging on the spot, a stretching routine of all major muscles including hamstrings, Achilles, quads and calves, and most important of all, your lower back.

Tuesday: Rest.

Wednesday: Run at half pace for eight minutes, walk for two minutes - repeat three times.

Thursday: Run at three quarter pace for two minutes, jog at half pace for four minutes, walk for four minutes. Repeat three times.

Friday: Rest.

At this point, it's important to understand what's happening to your body. You're about to start running for a more sustained, longer period of time with much smaller amounts of walking in between.

Splitting walking and running is easily one of the best ways to enjoy your fitness ride, without fear or becoming 'disengaged' or even injured. But it does drain you of energy.

So now that you're beginning to use much more energy, here are some top tips on ways to keep your energy levels high.

One of the great things about sustained exercise for 30 minutes or more each day, eating what you love becomes a less 'guilt free' option.

So, to increase the fuel in your tank, consider adding this to your diet where appropriate: Breakfast which includes cereal with chopped fruit or scrambled eggs on toast and milk or even a toasted tea cake and peanut butter. Fruit salad and yoghurt would also be a great option.

Snacks to take with you at work include ham, chicken or tuna salad, low fat yoghurts, fruitcakes or cereal bars, plenty of dried fruit and fresh fruit.

And for your big meal, go for a well-balanced option that contains carbs which comes from bread, potatoes, pasta or rice, and some protein, which you can find in fish, cheese, chicken and beans. Don't skimp on the vegetables. They're important too.

Next week, my goal for you is to run one mile continuously. To achieve that, you must follow this week's plan. And those meal tips will definitely come in handy, so it's important to get into a good habit now.