?"It's time to face the cryptic 'cross-training' references on my marathon schedule. What should I do? There's so much choice! Whenever I run more than about 14 miles my upper body gets tired, so I know I need to develop my core strength, but what's the best

1. SpeedThe Session: 4 x 40m sprints (with 3 mins recovery), then 4 x 300m sprints (with 6 mins recovery)Tony Minichiello says: "Speed training in heptathlon is crucial as there's an element of it in every event - just as there is in every race distance for running, whether you'r...

(runningwithus.com). "They can come back from their runs and pack in strength and conditioning work without going to a gym." Bands are colour-coded according to their thickness. A thinner band (normally yellow or green) offers less resistance and an easier

, or a perceived effort of "able to talk in short sentences", is easier to sustain, and less likely to lead to you becoming injured or stopping enjoying your runs. – VelociraptorLeave the strength training for another dayDo your core exercises as a

and stabilising muscles become very strong, and you develop a greater ability to absorb shock. Keeping the momentum going on a soft surface is hard work, so you are building muscles that will give you great strength and power."Core strengthGeorge Gandy, director

– so you must do some research on the course.Core Values With three disciplines to train for, the idea of adding core stability work to your training regime may fill you with dread, but strength and conditioning play a key part in Ironman training. Your

Use a foam roller for post-run recovery? That’s a smart move: this simple tool acts as a deep-tissue massager, working out kinks in overused muscles. But its benefits don’t end there – it can also build strength and stability. The roller has

and people around you).Anaerobic exercise such as weight-training has also been proven to give runners increased strength, speed, and core stability.When and how hard should I cross-train?If you’re new to the field of cross-training, take this advice on board

Hill repeats: help develop explosive strengthThe mild autumn weather is great for running and it’s tempting to use this as an excuse to skip the weights room. But as you pile on the miles, your need for strength training grows. Years of study show

and building core strength for good posture will help prevent injuries," says Pierce.Here's howAfter doing the envelope run (above), do two sets of the following: 30 seconds each of press-ups, squats and crunches; 60 seconds of planks and calf raises; 90