# The Loaded Joint > Straight answers on tendon injuries, building muscle, low energy and testosterone. Each article gives the answer first, then the trials and numbers behind it. All articles are written to answer one question each. The first paragraph of every article is the direct answer; the rest is the evidence and the caveats. Full text of every article: https://theloadedjoint.com/llms-full.txt ## Articles - [Is 400 testosterone low? What the number means at your age](https://theloadedjoint.com/is-400-testosterone-low/): 400 ng/dL is inside the normal range for men. What the harmonised range says, why morning timing and sleep move the number, and when free testosterone matters. - [How fast you can actually build muscle, in numbers instead of vibes](https://theloadedjoint.com/how-fast-can-you-build-muscle/): How fast you can build muscle: about 1 to 1.5% of body weight in year one, half that in year two. Real numbers by training age, and what sets the ceiling. - [Before you blame low testosterone, get screened for sleep apnoea](https://theloadedjoint.com/tired-not-low-testosterone/): Fatigue, low mood and low libido? Sleep apnoea lowers testosterone and mimics low T. How to get screened first, and how to test testosterone properly after. - [Hardgainer: why eating more is not working](https://theloadedjoint.com/hardgainer-eating-more/): Can't gain weight however much you eat? A Mayo Clinic overfeeding study shows where the extra calories go, and what works for hardgainers who have stalled. - [Low energy at 30, and why your labs being fine is not a result](https://theloadedjoint.com/low-energy-labs-are-fine/): Tired at 30 and told your labs are fine? A reference range is not a target. The blood numbers to ask for by name, and what to rule out before blaming hormones. - [Your tendon has not healed in six months because rest is the wrong prescription](https://theloadedjoint.com/tendon-has-not-healed/): Tendon still sore after six months of rest? Tendon remodels under load. The 12-week heavy eccentric protocol from Alfredson's trial, and how to run it at home. ## About - [About The Loaded Joint](https://theloadedjoint.com/about/)