What did @kmartfit actually say?
The creator told viewers to aspirate before every intramuscular injection, specifically to "pull back on the syringe about a quarter of an inch" after the needle is inside muscle. If blood appears, they say to pull out, swap the needle, and pick a new site. The framing is cautionary: "safer than sorry." That framing matters, because it positions aspiration as a safety requirement rather than an optional technique debate.
The video is aimed at people self-administering testosterone injections, likely cypionate or enanthate into the glute or thigh. These are real injections, not a clinic setting, and the creator is positioning this as essential practice. So the question is: does the evidence actually support making aspiration a rule?
Does the science back this up?
Not really, and this is where the video runs into trouble with current clinical consensus. The short answer is that aspiration before intramuscular injection is no longer recommended by most major health bodies, including the WHO and the CDC, specifically because the common IM injection sites used in TRT do not sit near large veins that pose meaningful embolism risk.
A 2016 review by Sisson in the Journal of Emergency Nursing summarized the existing literature and found no documented cases of IV injection resulting from failure to aspirate at standard IM sites. The ventrogluteal and vastus lateralis sites, the ones most commonly recommended for TRT self-injection, have no major blood vessels in the typical needle path. The CDC's immunization guidelines removed aspiration as a requirement for IM injections years ago, citing the lack of supporting evidence and the added discomfort it causes.
That said, the dorsogluteal site is closer to the superior gluteal artery, which is why some practitioners still recommend aspiration there specifically. So site matters.
What did they get wrong (or right)?
The creator gets credit for caring about safety and for walking through the mechanics correctly. If someone is going to aspirate, pulling back and checking for blood is exactly the right process. That part is accurate.
What they got wrong is presenting aspiration as universally necessary, with no context about injection site or current clinical guidance. Saying "this is very important" and "always be safer than sorry" without mentioning that major health organizations no longer require it is incomplete at best and potentially misleading for someone learning technique for the first time.
There is also a practical concern. Aspiration adds time with a needle in the muscle, which can increase tissue irritation, pain, and anxiety for new injectors. Teaching it as mandatory without qualification contradicts what most clinicians currently instruct.
- Accurate: the mechanics of aspiration described are correct
- Accurate: swapping the needle and changing sites if blood appears is the right response
- Misleading: framing aspiration as required without noting that evidence does not support this at standard IM sites
- Missing: no mention of which injection site they are using, which actually changes the risk calculus
What should you actually know?
If you are self-administering testosterone injections, the evidence-based recommendation from most current clinical guidelines is that aspiration is not required at the ventrogluteal or vastus lateralis sites. That does not mean it is harmful to aspirate. It means the risk it is designed to prevent is not well-documented at those locations.
The more important safety factors are: using the correct needle length for your body composition, rotating injection sites consistently, maintaining sterile technique throughout, and learning proper angle and depth. A 2019 paper by Cook and Murtagh in the Australian Journal of General Practice noted that injection site selection and sterile preparation carry far more weight for complication prevention than aspiration does.
If you are injecting at the dorsogluteal site specifically, the evidence for aspiration is slightly stronger given proximity to the superior gluteal artery, and your prescribing provider's guidance should take priority over any social media tutorial.
The bottom line: this video is not dangerous, but it teaches an outdated technique as mandatory. Follow the guidance of your prescribing clinician, not a 30-second TikTok tip, for anything involving needles.