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.
What Increases Your Risk. Most people get HIV by having unprotected sex with someone who has HIV. Another common way of getting the virus is by sharing needles with someone who is infected with HIV when injecting drugs. You have an increased risk of becoming infected with HIV through sexual contact if you: 1  Have unprotected sex (do not use condoms). 2  Have multiple sex partners. 3  Are a man who has sex with other men.  Have high-risk partner(s) (partner has multiple sex partners, is a man who has sex with other men, or injects drugs).
AGE. Although the HIV risk factors are the same for everyone, some groups merit special consideration because of their age. For example, in the U.S. new HIV infections are increasing among young men who have sex with men, especially young, black men who have sex with men (ages 13-24), despite remaining steady overall.ho is at Risk for HIV? HIV can be transmitted through certain bodily fluids: blood, semen (cum), pre-seminal fluid (pre-cum), rectal fluids, vaginal fluids, and breast milk.