When Group Training Isn't an Option
Training with a group is an excellent way to really enjoy your training. Time literally flies by when you are running or riding in a group. It will not always be possible for you to train with others, and when schedules conflict or the group session is canceled for some reason, don't dwell on the negative. Use the opportunity for training on your own to build your confidence.
You can of course, head for the health club to ride a stationary bike if your group ride fell through. Another option at the club might be a spin class, where you mount a stationary bike that uses a flywheel that requires constant pedaling so you can't coast. It's a tough but very effective workout, and you can usually just jump into a spin session at the last minute as long as there is a free bike.
A good way to cope with being alone on a solitary workout is to listen to music or the radio on a portable device such as an iPod. This is acceptable if you are running on a trail or in a park without vehicular traffic, but it is not safe on a city street. Never, ever, use such a device while cycling.
On a solitary run, use the time by yourself to visualize your race. See yourself coming out of the water, zooming down the road on your bicycle, and triumphantly crossing the finish line at the end of your run. Visualization is an important part of athletic success.
If you are on your own, try to find a trail or park where the scenery is attractive. Use the quietude to have an enjoyable rather than stressful workout.