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.
You're at high risk for HIV if: 1  You're in a relationship with a new sexual partner. 2  You don't know the HIV status of your new sexual partner. 3  You or your partner inject drugs.  You exchange sex for money or 1  drugs. Your partner is HIV positive.