His or her support is essential. Sitting on a bike seat for 14-16 hours offers a unique physical challenge. The key metric is total cumulative time in the saddle. Conditioning the legs involves more variety in order to build speed and strength. Endurance will represent either the easiest or hardest element of your training.
Endurance is said to be gradually built up over years of physical activity.
It's all a function of whether you've been in good shape the last 5 or so years. As a first-time rider, a key objective of your training is to simply convince yourself that you can do it. If you live in an area that's cold or rainy during the winter, you'll need to devise a strategy for training through it. I recommend riding on rollers . Learning to balance on them isn't as hard as you might think.