My journey from a life of pseudo foods, pharmaceuticals, and obesity to one of health has mostly been motivated by a numbers game. It's not like I was just sitting around one day and said "Hey! I think I'm gonna train for a foot race or a triathlon!" No. For me it was about weight management. Everyday I step on the scale at least twice. Once after breakfast and once after my exercises. Then I reflect on what I did over the past 24 hours. Gradually over time I figured out that the simpler I made my routine, the easier it would be to tweak for changes so that I could determine what works for me.
Looking at the chart over recent weeks I can see that my weight is trending up slightly. I can conclude several possible reasons for this. A) I'm gaining muscle mass, which my recent bench press PR would support. B) I'm eating too much ice cream, which I do tend to consume to regulate my weight upwards whenever I regularly drop below 160 Or, C) Too much processed foods, including meats, since marathon training can make me a bit ravenous and indiscriminate with my food choices.
All in all, it's some combination of the 3 and if I start trending above 170 I know exactly what to do to bring it back down. A) Stop lifting weights and/or increase cardio intensity so as to burn muscle mass. B) Ditch the ice cream. Or C) Decrease my percentage of processed foods. Again, the course of action would undoubtedly be some combination of the 3.
The idea I'm wanting to present here is just that if weight management is important to an individual, then it requires monitoring and actions to regulate it. It's kinda easy really and it just takes a few minutes a day. I learned what works for me and I believe everybody can learn what works for them. Some people may be able to do it with little to no exercise and almost all with dietary adjustments, others may be the opposite. Probably, I believe, it will be some combination of the two and you just have to establish a routine then tweak it to get the results you want.