Cycling is the most expensive sport in triathlon. Initially you may be able to rent and borrow bikes, but eventually you will need a bike, and even a low-end road bike is going to be at least a few hundred dollars used. At some point you will want cycling pedals and shoes. These allow you to get more power from pulling up as well as pushing down, and also offer low flexibility which can improve the efficiency of riding. There are many pieces of other gear that are outside the scope of this post, but some items I have discussed and I will be discussing others in other posts.
In most places, at some point in the year the weather will be such, or the road conditions (snow) will be such that you will want to ride indoors. I love a good cycle class in a gym, and this can be a great, efficient way to fit a workout in, say during a lunch break. However, if you want to avoid the monthly gym fee, indoor trainers allow you to ride your own bike inside your home or garage. This also has the advantage that you can be riding your own bike, in the same or similar position that you ride outside. It certainly isn’t the same, but it is far closer than most indoor bicycles in a gym.
I covered more about indoor trainers in the post I linked to above. At that time I had recently purchased a fancy trainer that allows you to do computer-based rides, such as a particular course, and between the trainer and your computer or phone, the resistance is increased and decreased, etc – and you ride in real time against other human beings. I ended up deciding to save the money and return the trainer. It wasn’t right for me at that time in my life, and still isn’t, but I know that for many people it is a great training tool.
So, while cycling is more expensive, and one could spend multiple thousands on fancy equipment, training for the middle sport in triathlon doesn’t have to break the budget. You can also make a plan to work on it over time. Maybe you start buy using whatever type of bicycle you may already have, or you purchase a used, cheaper road bike. Meanwhile, you can keep your eyes out for a used trainer – anything that will allow you to ride that bike at home. Or, if you are already hooked, you may know the exact equipment you want, and it makes more sense to save up to buy the item that will last you for years and years of loving the Trilife. The fair assessment that works for you and your desires is the most important thing!