I don't understand mechanisms of heat/cold intolerance in thyroid disorders help me

[Day 77]

Today's Workout: AM CSP Practice, sprint free day
Summary:

• WU: 
• 200 swim
• 200 kick no fins
• 200 pull no paddles
• 100 swim (as written was a 200...idk what the lane decided)
• Pre-Set: straight through, breaks indicated, if I didn't put a pace time it's because I don't know what we did it on
• 8 x 50 stroke/free by 25 @ :55 (I did 4 fly, 4 back)
• 1 x 100 free
• 4 x 25 choice (back) descend 1-4
• (break)
• 4 x 50 kick w/ fins choice @ :50
• 1 x 100 swim w/ fins @ 1:30
• 4 x 25 kick w/ fins MAX @ :30
• (break)
• 2 x 50 free @ :45
• 1 x 100 swim @ 1:40
• 4 x 25 break outs free 
• Main Set: straight through, all free
• 1 x 50 @ :40
• 2 x 100 easy @ 1:40
• 2 x 50 @ :45/:40
• 2 x 100 easy @ 1:40
• 3 x 50 @ :50/:45/:40
• 2 x 100 easy @ 1:40
• 4 x 50 @ :55/:50/:45/:40
• 2 x 100 easy @ 1:40
• 5 x 50 @ 1:00/:55/:50/:45/:40
• 2 x 100 easy @ 1:40
• WD: lol no time
• Total Distance: 3750 SCY

Hit Rate: 82/90 (91.1%)

Already dreading the trainer ride tomorrow and I haven't even taken my exam yet yay. Back to studying.

Much love,

Jess