Testosterone can be administered parenterally , but it has more irregular prolonged absorption time and greater activity in muscle in enanthate , undecanoate , or cypionate ester form. These derivatives are hydrolyzed to release free testosterone at the site of injection; absorption rate (and thus injection schedule) varies among different esters, but medical injections are normally done anywhere between semi-weekly to once every 12 weeks. A more frequent schedule may be desirable in order to maintain a more constant level of hormone in the system.  Injectable steroids are typically administered into the muscle, not into the vein, to avoid sudden changes in the amount of the drug in the bloodstream. In addition, because estered testosterone is dissolved in oil, intravenous injection has the potential to cause a dangerous embolism (clot) in the bloodstream.
By the time of the VH series, Commodore sales were beginning to decline. Holden's six-cylinder engine , which was carried over from the Kingswood , could trace its roots back to 1963 and was no longer competitive.  Continual improvements made to Commodore's Ford Falcon rival meant the VH was not significantly more fuel-efficient or better performing despite the smaller size.   This was curtailed by the absence of any major powertrain revisions by the time of the VH and the lack of visual departure from the original VB.  Holden also had to deal with the influx of their own mid-size Camira from 1982, which presented comparable interior volume with lower fuel consumption, and for less than the Commodore pricing point. Camira sales were strong initially, but as fuel prices had stabilised, buyers gravitated away from Camira and Commodore towards the larger Falcon, which overtook the Commodore as Australia's bestselling car for the first time in 1982.