1 Isotonic -a muscle fiber contraction in which force production is unchanged when the muscle contracts causing movement of an external load.  Isokinetic -a muscle fiber contraction in which force production of the contraction is sufficient to overcome the external load.
HIV/AIDS. HIV Risk Behaviors. The risk of getting HIV varies widely depending on the type of exposure or behavior (such as sharing needles or having sex without a condom). Some exposures to HIV carry a much higher risk of transmission than other exposures.
A healthcare practitioner may also order an HSV antibody test when someone has another STD and is at risk for the infection. Risk factors include having multiple sex partners, having a sex partner with herpes, being infected with HIV, or being at risk for HIV because the person is a man who has sex with men.