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.
Anyone who is sexually active risks exposure to a sexually transmitted infection to some degree. Factors that may increase that risk include: Having unprotected sex. Vaginal or anal penetration by an infected partner who isn't wearing a latex condom significantly increases the risk of getting an STI. Improper or inconsistent use of condoms can also increase your risk. Oral sex may be less risky, but infections can still be transmitted without a latex condom or dental dam.