I'm donating blood on Wed., how long would you wait before biking again? Obviously I won't go Wed. and may take Thurs. off from biking (but will walk 3-4 miles). My schedule has normally been 2 days on (one walk, one bike), a day off. I did both weekend days (14 miles on the bike Sat. and 3.5 walking Sun.) but am doing another bike day today as I have other things scheduled on Tues. that will result in getting home too late to bike and the blood donation Wed.