When you take exogenous testosterone (the synthetic anabolic hormones, known as steroids), your natural hormone production (endogenous testosterone) is suppressed because your body is getting plenty of testosterone. It is not advised to take steroids habitually because of their many side effects, which we talk about below. So when you go off the steroids, your body’s natural ability to produce testosterone is compromised. Most people use steroids in “cycles” to prevent building a tolerance but also to allow the hypothalamic-pituitary-gonadal axis (HPTA) — the system that regulates hormone production — time to increase testosterone production after use. But with any steroid use, the flood of synthetic hormones throws your body off balance. Once the user ceases anabolic steroid use, the body is slow to recover to normal levels of testosterone. Aside from ill health, the post-steroid user can be vulnerable to muscle mass loss and increased oestrogen levels.