I’m giving blood tomorrow afternoon. I’ve given plenty of times in the past with few side effects, typically some tiredness that day and good to go again in 24 hours. Once I did almost pass out while donating. That was fun. Anyway.
How do you find donating blood impacts your training?
I donated both plasma and blood in the past while training for running events (half/full marathon) and found that the plasma donations had almost no effect.
Like you seem to do, I tended to go easy after donating blood. Not that anything ever happened; it just felt like a good precaution.
(Unfortunately, where I live now there’s no possibility to donate blood.)
Hey @Jason_Blakeburn ,
Congratulations on donating blood! Your training will be impacted for a short period.
Here’s an article for you to read:
Cheers,
Spencer
I’ve found that donating whole blood knocks me back noticeably for a week or so as my red blood cell recovers from the donation. I’m probably fully back at 100% after two weeks.
For that reason, I now donate platelets, which takes a lot longer at the time of donation, but has much less impact on my ability to train or otherwise be physically active. I’m usually good to go after one day of rest after a platelet donation, which I think is mostly recovering from fluid loss.
Yeah, but when they put it back in for the race season it feels great 
THAT’S A JOKE
Don’t do it. Illegal and incredibly risky.
The disclaimer made this joke funnier. 
I’ve only given blood once in-season. I did a run on the indoor gym track the day after and found I got flushed and clammy. Took maybe 2 or 3 days then I felt back to normal. That was about 10 years ago.
Gave blood last time a couple years ago. I just took it easy for a couple days after and had no issues.
In general it’s a good idea to give yourself about 3 off/easy days to recover and then get back into it.
I give blood every two months. I usually do my normal workout that morning, give blood at 3PM, then I drink a lot of fluids and take a rest day the next day, and after that I have no issues.
Norm
If only I’d spent time at altitude first!
I was going to donate this week but when I arrived at the location, they’d given me the wrong address. Rescheduled for my next rest week. Might end up putting it off until post-season plus COVID cases are surging locally. 
LMAO - Also the immediate explanation is too funny!!
When donating whole blood, I feel the difference for about a week. If I am in heavy training I have no way to really “know” if it results in a longer-lasting impact.
I switched to donating platelets. (same as @way9e0 )You are allowed to donate platelets 1/week. I go once every 2-3 weeks typically. I schedule them on my recovery days, so typically Monday. Works well because they need a lot of platelets, and I can donate more often, and I keep all the RBC’s so no training impact. It takes about 2 hrs with needles in both arms. Be ready to pick a movie to watch and NOT scratch your nose!
I ride there on my Brompton to donate and then every time get into a discussion that I shouldn’t be riding after donating, etc…
Just be sensible and listen to YOUR body. I donate when I can but follow the same approach as Gunnar and others.
On the day train first thing.
Eat and hydrate sensibly all the way up to the session. (In the UK, they make you drink a pint of water before hand too)
I then treat the return journey as a bit of active recovery and pootle back at a really low intensity.
Usually good to go next day.
It sort of depends on what you are used to. I find that works for me, others will baulk at it. But if you’re not sure, then don’t do it and save it for your off season.
Some eat cake, or drink beer at the end of their season, but a true Sufferlandrian gives away their blood?
Much depended on if doing a single- or double-unit donation. The single would knock me out for a day or two—Suffering still possible but at a reduced intensity. The double would take a bit longer to fully bounce back from; once, an entire week.
There are other factors, I’m sure that people more knowledgeable than me can speak to, but I would think that if you’ve a history of donating, you should be fine in no time. (Because I know GvA does not take sick notes.)