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).
The only 100% effective way to prevent sexual transmission of HIV and STDs is through abstinence - avoiding all vaginal, anal and oral sex. Using a latex male condom or a female condom can greatly reduce, but not entirely eliminate, the risk of HIV and STD transmission. Abstinence is the only method to completely eliminate the possibility of sexual transmission of HIV or STDs. No. Only condoms reduce the risk of pregnancy, STDs and HIV.