SARMs (Selective androgen receptor modulator) are the the best options for bridging.. Ostarine, s4, LGD 4033 are sarms. They're much less suppressive than steroids and have similar effects. Since they're selective, they only effect skeletal muscle tissue which is awesome. Gw501516 is a nice addition too. Also look into peptides like ghrp 2/ghrp6/ipam and cjc 1295 mod grf