Losing weight around work and family life

Hi

I work for an IT company as a Solutions Consultant or Sales Engineer. This means that I am involved in creating solutions to meet a customer's requirement, including providing demonstrations and technical advice. I also get involved in support of systems once they are installed. The company is based in the US and as such I frequently have calls late in the day (early evening) to discuss issues. My responsibilities are mainly in the UK but I have to support our partners across Europe and into Russia as well.

This involves a lot of travel, primarily within the UK but across the entire area I support, and occasionally to America for training and meetings. At the same time however I am also based from home so when it is quiet I benefit from being able to see the kids more and do things such as take them to or pick them up from school. Very occasionally weekends are affected with travel arrangements. This unpredictable work pattern makes it difficult for me to schedule anything on a regular basis.

I know I am overweight and want to do something about it, but I always use the excuse of work to stop me doing it. I used to enjoy mountain biking and sailing, and would like to get back to these. I also want to be able to do day to day things and play with the kids without getting out of breath. I know that it will also affect my future life if I don't sort it out. I want to lose between 3 and 4 stone to get me back to a sensible weight.

Does anybody have any suggestions of things that they have done in similar situations? I have cut back on puddings and also reduced the amount of fast food that we eat, but when you are always on the work and junk food is the only available food around it is difficult to avoid.

I have an appointment to visit a gym in a week but last time I went to a gym I got bored. Any other ideas?