Why you shouldn't take pre workout supplements?

Pre workout supplements is a generic term for a range of bodybuilding supplement products used by athletes and weightlifters to enhance athletic performance. It is taken to increase endurance, energy, and focus during a workout. Pre-workout supplements contain a variety of ingredients such as caffeine and creatine, ranging by product. It can be taken in a variety of forms including capsules and powder. The first pre-workout entered the market in 1982, and since then they have grown in popularity. Some pre workout supplements contain ingredients linked to adverse effects. Although these products are not banned, the Food and Drug Administration (FDA) warns consumers to be cautious when consuming pre-workout.

Pre-workout supplements are available in different forms including tablets, capsules, liquids, powders, and bars. A number of common ingredients are used. There is considerable overlap between the ingredients used in pre-workout blends and other supplements for weight loss, improving mood, life extension, or as purported nootropics or aphrodisiacs, although certain ingredients tend to be found only in products intended to assist in bodybuilding or athletic training. Some ingredients such as caffeine, creatine, and β-alanine are found in nearly all pre workout supplements blends, but each branded product is a "proprietary blend" with an average of 18 different ingredients, the exact composition, and proportions of which can vary widely between different products.

Methylhexanamine, also known as DMAA, is another stimulant that was widely used for some time as an alternative or pre workout supplements to caffeine. The FDA has warned that DMAA "is known to narrow the blood vessels and arteries, which can elevate blood pressure and may lead to cardiovascular events ranging from shortness of breath and tightening in the chest to a heart attack". DMAA is also considered a prohibited stimulant by the United States Anti-Doping Agency. Following the widespread banning of DMAA, it has in some cases been replaced by similar compounds such as DMBA, octodrine, tuaminoheptane, or DEPEA, which are associated with similar side effects.