Thank you for your question – another really good one on this forum.
Dr Alan has given you an excellent summary of the treatment option and I would only add that what you plan to do really impacts on your treatment decision.
If you are keen to return to a twisting/turning sport, then an ACL repair should be considered. But if running and cycling are your main areas of interest, then it is not desperately necessary and seeing a physiotherapist to build up muscle after the injury might be the way forward. Indeed, I have had a number of patients who decided against surgery as they did not feel it was necessary, and they continue to be physically active and sporty to this day.
Great question and again shows how important individualisation of medical care is rather than following general rules!