Looked it up and hair follicle testing won't work for steroids, hgh or any of the other things we typically associate with PEDs (epo, testosterone, etc.). This is why USADA and WADA don't use those tests; they use blood and urine samples and compare them over time to create what they call a genetic passport. They can obviously test for the drugs that come up on their blood and urine tests but by taking specific measurements of hormones, blood counts and other things they can compare to see if you are taking masked substances that are changing the way your body naturally is.