What's the difference between "run" and "jog"? And why "a" was used before "run"?
Answer from a Native speaker
"Jogging" is running that is usually done at a slow and steadier pace than a normal run. "Running" often implies that someone is running for a race or for sport, while "jogging" usually refers to running for leisure. The article "a" is used before "run" here because the word "run" is used as a noun, along with "walk" and "cycle" which are also nouns in this sentence. Since each of these words are used as nouns, you can use "a" in front of them. Ex: I went for a run earlier this morning. Ex: He's not home, he's on a walk with his dog.