Hi, I tried a 800m run yesterday. My last record was 2:14 for the 800, and 4:47 for the mile, and 4:35 for the 1500. I just ran a 2:04 yesterday with splits of 1:00.44 and 1:04.02 acording to my gps watch. My friends timed me and said I got 1:01 on my first lap and 1:03 on my second. I am confused why I improved this much. I did a lot of interval work, does this mean my time would get worse if i started doing more base/threshold/tempo workouts from now and only one interval workout like 4x800 with rest until i feel like it? (Other examples: 8x400 with 1:25 rest, 16x200 with 200m recovery walk, and 3x1k with rest until i feel like it.) I did mostly these workouts and not much of a base but some, does this mean my time i achieved is only going to last me temporarily or will I be able to improve from this time doing more tempo/threshold workouts?