30/15's into Threshold #4

Duration 33:30 TSS 39 IF 0.84

04:00 @ 45% FTP - 75% FTP
3x
00:30 @ 65% FTP,
00:30 @ 89% FTP
02:00 @ 55% FTP
10:00 @ 75% FTP
6x
00:30 @ 125% FTP,
00:15 @ 65% FTP
04:00 @ 85% FTP - 100% FTP
02:00 @ 55% FTP
04:00 @ 70% FTP - 45% FTP

After warming up, complete 10 minutes at Zone 2 Endurance, followed by 6 x 30sec on / 15sec off, leading into 4 minutes at threshold.