I thank both of you for the replies.
Let us take another example. I am training at a gym 3 times a week. I am training on Mondays, Tuesdays and Fridays.
I always train at least for 90 minutes. Sometimes I exceed the 90 minutes limits and train 100 or 120 minutes.
The first thing I do is to train using a bicycle or a treadmill. This is to warm up the body; it is good for the cardiovascular system of the body, as well. Afterwards I train different muscles using machines. The gym is flooded with all sorts of machines.
1. At the beginning, I train bicycle/treadmill.
2. In the beginning, I train bicycle/treadmill.
Which is the corret one in this context?