I did a couple 50 meter flies in low and mid 6. Then went on to do 8x300 averaged 55.6. With a very slow jog for 90 seconds at 11 min mile pace. Felt relaxed but was tired at the end, felt like I could have done 2 or 4 more. Can I break 5 for the mile? I have ran a sub 5 before just been a really long time about 6 years and trying to get back in shape again.