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.
Sex and Intimacy With HIV. If you or your partner has HIV, know this: With treatment and protection, you can have a long, healthy life together -- and have good sex together, too. Make Sex Safer. You have to use protection, whether you're HIV-positive or you're in a mixed-status couple, in which one person has HIV and the other doesn't. Use condoms every time you have sex. Unprotected sex is the most common way of spreading the virus. Male and female condoms dramatically lower the chances of transmitting HIV.