T Nation

A Question About Injection Frequency

I see alot of guys on here talking about injecting slow esters like enenthates and cypionates eod and e3d.Now I was under the assumption that these kept the test elevated for at least a week and could be administered once weekly.So why inject it so frequently.

Just looking for some knowledge on this so i can better my using experiences thanks.

blood levels are kept more stable at 2 shots per week than 1 shot per week,i dont know anyone who injects long esters e.o.d but im sure some one here will have the answer

I haven’t heard of EOD for such long esters, either. Who’s doing that? E3D is a good schedule for cyp and enth half-lives. You can get away with twice a week, too, though.

Those esters keeping “test elevated for at least a week”…definitely not. Enanthate has a half life of 10.5 days, cypionate of 12, so there would be enough reduction after 7 days of blood levels of testosterone that you would want a more frequent injection schedule.

Do a google search for “PCT calculator”

Use whatever kind of test you like and use the same amount total per week but change the injection frequency and compare E3D to once per week. Check out the huge fluctuation in the amount of test in your body throughout a cycle.

For simplicity’s sake, I will inject longer esters 3X week, going MWF. This is just to avoid having to worry about it over the weekend.

Great info thanks,now another question.What is the smallest guage needle you guys would use to inject a test mixture.I have used 23s before and have heard of guys drawing with 20s and injecting with 25s.Now Im talking about test E and cypionate mixes and also masteron and deca.

23g & 25g are the most popular choices, but oil will flow through smaller gauges.

Mine is a little more sick… If the best way was to inject once a week i would but as you can do more, i do - this is simply down to the fact i like injecting. I always have.


I know what all the sites claim the various half lives of the different esters are. I subscribe to a different interpretation. I have mentioned this before. Sadly, I cannot provide an empirical link to back up this viewpoint.
I have long held to the notion that if you take the number of carbon atoms in an ester and multiply this by a factor of .7 you get your functional half life.
Tren Ace, 2 carbons = 1.4 day half life. This is the reason Ace is so much better as an ED than an EOD; those who have tried it both ways will testify.
Test Prop, 3 carbons = 2.1 day half life. Everyone knows to hit Prop EOD.
Nandrolone Deca, 10 carbons = 7 day half life. This is why you can justifiably pin Deca just once a week.

The interesting ones are the big two enanthate and cypionate. 7 and 8 carbons respectively, 4.9-5.6 days respecitvely. This is why E3D or twice a week work so well for Enan and Cyp. Lots of TRT protocol calls for weekly Cyp injections. From the chart you can see you can almost get away with it. My very first Test cycle, I used Cyp and I hit it just once a week. Because in part I too read the notes Cortes sited above that Cyp’s half life was 12 days or so. If that were the case once a week would have been fine. My results were decent. However, then I stumbled across this info about the .7 factor. My next Test Cycle I do hit it twice a week and that was a much better Test Cyp experience for me than just once a week.

Bottom Line you can always inject more frequently than called for. You can hit Cyp and Deca ED if you want. If you don’t then I believe the .7 factor protocol is the best way to fly.

I like that theory, saps. Good post.

Yeah its actually slightly more than a theory too. Back in 05 or 06 there was a link to all the technical stuff I’m totally just glossing over in layman’s terms. However, the link died in 07 and for the life of me I cannot find anything anywhere that testifies and verifies what I now believe about half lives. Not the biggest deal in the world here of course. Its not like I believe the earth is flat or anything. After all most people know or at least will hear to hit the different esters at the frequency purported by the .7 factor. Its just when someone asks why its a little nice to have some genuine science behind why. As opposed to merely my opinion.
Either way, I’ll still just keep telling people what I think, most people are getting it right on their own anyway.