All energy systems generate ATP, which is the fuel for muscle contraction.
The intensity and length of activity determines which energy system is the primary producer of ATP.
For bouts of exercise or activity 3 minutes and longer, ATP is produced via oxidative phosphorylation, which is part of aerobic respiration and involves glycolysis, the Krebs Cycle and the Electron Transport Chain.
In an anaerobic environment (lacking oxygen) there are two primary forms of ATP production.
For bouts of moderate to intense exercise or muscle activity lasting from about 30 to 180 seconds, the glycolytic energy system is employed. Glycolysis produces a small fraction of the ATP that oxidative phosphorylation does, and results in the formation of lactic acid within the muscle.
Creatine comes into play in the third energy system: the ATP-PC system, which is used primarily during bouts of intense exercise lasting less than 30 seconds.
some sources have subcategories within each of these, or use slightly different terminology. For example: The ATP-PC (phosphocreatine) system is also called the phosphagen system. Read more here:
As with any type of training, you don’t want to perform work that will cause conflicting adaptations. This is a reason why I stopped running cross country while simultaneously trying to train anaerobically for baseball in high school. The results I got in each were dampened by the other. That being said, light cardio not done at a high volume is unlikely to negatively affect you. I walk around 2 miles a day around campus during the school year and haven’t noticed any negative effect from this on strength gains or explosiveness. Unless you’re going for 10 mile hikes multiple days per week, I wouldn’t worry.