Rest Day Before Labs?

[Jack3d_Wabbit28]

Just wondering how necessary a rest day before getting bloodwork is? I’ve noticed my liver enzymes being higher when I don’t rest but that’s about it. I always run GGT so figured it wasn’t that important to rest. What are you all doing?

Working out helps me out mentally as well as physically so I hate rest days lol.

 

[HFO4]

Historically, over lots of years, I’ve seen results can me much more accurate when properly rested and hydrated

 

[PRorER]

Historically, over lots of years, I’ve seen results can me much more accurate when properly rested and hydrated

This is very true. Anytime I’ve trained at night and got bloods next morning fasted my liver and kidney values are always slightly elevated. Recently I’ve been scheduling them bloods on Mondays (no training Saturday or Sunday) and they always come back solid

 

[Jbswole40]

Definitely makes a difference, especially on certain markers.

 

[Phill]

1. Liver enzymes (AST, ALT, CK) – These can spike significantly from muscle breakdown, especially after resistance training or intense cardio.
   
   • AST and ALT are found in both liver and muscle; intense exercise can elevate them independent of liver health.
   • GGT is more liver-specific and less affected by exercise, which is why you see less change there. Still, overall liver enzyme interpretation can be skewed.
2. Creatine Kinase (CK) – Huge elevations after training; not a liver enzyme, but often checked in panels. High CK could prompt unnecessary concern if doc doesn’t know you worked out.
3. Inflammatory markers (CRP) – May increase temporarily.
4. Kidney markers (creatinine) – Slight increase possible due to muscle breakdown and dehydration.
5. Testosterone/Cortisol – Acute exercise can raise total testosterone temporarily (especially in athletes), then drop later depending on timing; cortisol rises with intense/long training.

General recommendations:​

• At least 48 hours of no intense training before bloodwork if you want a “true baseline” for AST/ALT/CK.
• If that’s impossible, a light rest day before is still better than training the morning of the test.
• Hydrate well the day before to minimize dehydration effects on kidney markers and hematocrit.

Ultimately, if you always train and never rest before bloods, your baseline becomes “trained state” values
just be consistent so you can compare apples to apples over time, and make sure your doctor knows you didn’t rest so they don’t misdiagnose.

 

[REHH]

It definitely makes a difference

 

[Trippy802]

Just wondering how necessary a rest day before getting bloodwork is? I’ve noticed my liver enzymes being higher when I don’t rest but that’s about it. I always run GGT so figured it wasn’t that important to rest. What are you all doing?

Working out helps me out mentally as well as physically so I hate rest days lol.

I mean it really boils down to if you want accurate liver and kidney readings. It’s very well known they raise when we train hard 1-2 days before. I’m the same way with training and my mental health. Training has saved me from my past life and I don’t like taking days off either but they are pretty important for things like this.

 

[FearsomeCOR]

I never take a day off before, I’m just aware of how it’ll affect certain markers. I get a Cystatin c and GGT anyways to assess kidney and liver function.

 

[Nood]

I typically take 2 days off before labs. What it takes for my liver enzymes to be back in range from lifting

 

[Startingover]

Nvr was aware of labs being effected from hard traing day before?
Good info.
I'm in dame boat far as days off go .
but for true reading
Sacrifice we all can make in sure.
If we just need to make trip to gym?
How bout some stretchin,hanging,etc shit like that
Mentally you were there and won't beat us up to bad..

 

[Wiseguy]

1. Liver enzymes (AST, ALT, CK) – These can spike significantly from muscle breakdown, especially after resistance training or intense cardio.
   • AST and ALT are found in both liver and muscle; intense exercise can elevate them independent of liver health.
   • GGT is more liver-specific and less affected by exercise, which is why you see less change there. Still, overall liver enzyme interpretation can be skewed.
2. Creatine Kinase (CK) – Huge elevations after training; not a liver enzyme, but often checked in panels. High CK could prompt unnecessary concern if doc doesn’t know you worked out.
3. Inflammatory markers (CRP) – May increase temporarily.
4. Kidney markers (creatinine) – Slight increase possible due to muscle breakdown and dehydration.
5. Testosterone/Cortisol – Acute exercise can raise total testosterone temporarily (especially in athletes), then drop later depending on timing; cortisol rises with intense/long training.

General recommendations:​

• At least 48 hours of no intense training before bloodwork if you want a “true baseline” for AST/ALT/CK.
• If that’s impossible, a light rest day before is still better than training the morning of the test.
• Hydrate well the day before to minimize dehydration effects on kidney markers and hematocrit.

Ultimately, if you always train and never rest before bloods, your baseline becomes “trained state” values
just be consistent so you can compare apples to apples over time, and make sure your doctor knows you didn’t rest so they don’t misdiagnose.

One thing I noticed was elevation in PSA numbers. I did one hour of cardio on stationary bike and the PSA number spiked. I did a re-test a day later and the numbers were back in range.

 

[GYMnTONIC]

Very important to take time off for accuracy.

48-72 hours for true results.

 

[Meetketchup]

1-2 days off as stress free as possible, good sleep and 100% hydrated

 

[Old_Ironman1972]

This is great info. I've never understood why my enzymes where slightly elevated as I take milk thistle. I had no idea training makes a difference. Staying well hydrated seems to be more commonly known. I'm curious how much it will change my results. Thanks guys.

 

[Jack3d_Wabbit28]

Some great information here!

 

[SamPedd18]

Just wondering how necessary a rest day before getting bloodwork is? I’ve noticed my liver enzymes being higher when I don’t rest but that’s about it. I always run GGT so figured it wasn’t that important to rest. What are you all doing?

Working out helps me out mentally as well as physically so I hate rest days lol.

I’ve always taken 48 hours off before labs and increased my water intake.

 

[Moya Squats]

I'm confused. Wouldn't you want your labs to reflect the state your body is usually in? I'd think you'd not want to take more time off than normal to get the most accurate labs of how your body is on the average day That seems the most accurate to me.

 

[FearsomeCOR]

I’ve always taken 48 hours off before labs and increased my water intake.

If you’re having to increase your water intake for good labs, that’s a sign you’re not hydrating enough on a regular basis.

 

[SamPedd18]

I'm confused. Wouldn't you want your labs to reflect the state your body is usually in? I'd think you'd not want to take more time off than normal to get the most accurate labs of how your body is on the average day That seems the most accurate to me.

If you get labs the day after a hard workout your body hasn’t totally repaired itself so things such as liver function is going to be skewed. It’s the same as if you’re going for labs at your TRT Dr and they want to test you in your trough but you pin an hour before labs. Your results are skewed. All you’re doing on the test days is just letting the body repair and flush all the junk out better you get your labs done. That make any sense lol?

 

[GYMnTONIC]

I'm confused. Wouldn't you want your labs to reflect the state your body is usually in? I'd think you'd not want to take more time off than normal to get the most accurate labs of how your body is on the average day That seems the most accurate to me.

No it's not accurate. Creatinine for instance is 100% related to dehydration and muscle breakdown. Also your organs, kidneys and liver will show stress from the training, potentially dehydration and muscle breakdown, etc. It is not optimal. If you went out drinking and using cocaine, it's gonna show your body as a mess. Meanwhile that is a photo of that very given time and day only. If you wait 2 days and test your body will have a realistic snapshot of the true function, not the inebriated results.

When you get labs you want an overall picture of the "actual" body function. Temporary changes are not "actual", they are temporary.