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Supplements for Women

The Fit Woman’s Guide to Supplements

Think some products are strictly for guys? Here’s what you need to know about five supplements you may have previously considered “off-limits.”

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Although you may not always realize it from the marketing campaigns, there’s more to a woman’s supplement needs than a trusty thermogenic fat burner. Women don’t just want to lose weight — we want to shape our physiques and build a body that’s strong and makes us proud.

To accelerate that effort, there’s a “secret” most women don’t realize. Some of the very same products you find in the kitchen cabinets of a typical bodybuilding-obsessed male may help you with your exercise goals, too. A lot.

Sure, much of what he’s taking promises to promote “massive muscle growth,” but you don’t need to worry about suddenly expanding to inside-linebacker proportions when you take them. “Physiologically speaking, as a woman, your body simply won’t respond in the same way,” explains ACSM-certified exercise physiologist and sports dietitian Wendy Bazilian, DrPH, RDN. “Oftentimes, a supplement has more than one potential benefit. And the thing is, in order to get the benefits you’re working toward, you actually have to do the work and training along with eating to fuel and supplement your efforts. With the right supplement, and the proper training and recovery, your body will respond by helping you perform while you also firm, shape, tone, and yes, build muscle as you want it.” 

6 Oxygen-Approved Supplements

1. Whey Protein Powder

Whey has gained even more acceptance as a way to provide a protein lift to smoothies, oatmeal and even pasta sauces, but it’s long been a familiar part of sports supplementation programs. “It’s one of the two proteins found in milk, representing about 20% of milk’s protein,” says Bazilian. “It digests faster than other proteins and has received more research attention for its role associated with exercise performance and muscle recovery. As a result of its quicker digestion, it enters the blood stream and “gets to work” where it’s needed faster.” Whey protein also has a higher amount of branched-chain amino acids (more on them below), which are critical to muscle growth and repair, and may help with recovery by helping reduce muscle soreness. 

Why He Takes It: We mentioned that whey digests quickly, but that means that once it hits your stomach, it starts releasing its amino acids into the bloodstream. This is beneficial because it provides not only fuel for those muscles during workouts to optimize performance but also ensures that necessary amino acids are present during and after workouts to begin to repair the damage caused by training — and to build new muscle if the muscles have been sufficiently challenged.

Why You Should Consider Taking It: Whether or not you’re interested in grooming your muscles (note that we didn’t say growing), whey protein is a supplement that can provide your muscles energy to help fuel performance (a good workout) and the essential compounds vital to your body’s recovery.

Try: one scoop (20 grams) of whey one to two hours before a workout as part of a meal or snack, and another within 30 to 90 minutes after a hard workout. “Prioritize the post-workout scoop if only using one, which is perfectly fine if you are fairly active,” says Bazilian. “You can also use one scoop first thing in the morning or between meals as part of a snack.”

2. Casein Protein Powder

Casein protein is one of the proteins in milk (it makes up 80% of milk’s protein), that becomes more gel-like in its texture. Casein is a supplement that curdles in milk or helps create texture in yogurt and cottage cheese, and helps make cheese solid. 

Its super power is that it has a slower release and effect in the body — this means that casein is broken down into amino acids, which are released more slowly into the system via digestion/metabolism. “While whey is often considered superior because of the kinds and quantities of amino acids involved in building muscle tissue, casein is credited for its longer-lasting muscle-preserving effect,” explains Bazilian. 

Why He Takes It: Caesin is a supplement often used to boost protein for fitness goals, like muscle-building and to support endurance fitness.

Why You Should Consider Taking It: If you’re looking to lean your body, which may also include shedding a few pounds, while you maintain or build muscle, casein may help. “These benefits are not sex-specific,” says Bazilian. “Muscle-building power does not necessarily mean muscle bulking — but it can mean being stronger, learner and more powerful. Longer-lasting energy through slower-acting release of blood sugar is a yes-brainer for staying even-keeled and supporting endurance exercise.”

Try: Many people recommend casein as an evening or nighttime supplemental protein. “There’s some evidence that it may help preserve muscle better while you sleep,” says Bazilian. “Otherwise, you could use casein as a pre-fuel part of a meal or snack at least 60-90 minutes before exercise or as part of a post exercise recovery snack or meal.”

3. Creatine

Your muscles contain creatine, and it’s found in the seafood and meats you eat for dinner. Creatine is an amino acid and its job is, via some chemical exchanges, to create quick energy in cells. Taking supplemental creatine provides the resources to make more energy, which helps your muscles work better for longer. 

Why He Takes It: A guy takes creatine to max out muscle size because he can do more reps or more time, which can equate to more strength, size and performance boost. “Creatine helps the body do this in a number of ways,” explains Bazilian. “It helps him work out harder and longer, it increases levels of certain hormones that are critical to gaining muscle mass, and it draws fluid into muscle cells, physically forcing those cells to stretch. It may also help him stay hydrated, which can potentially help prevent muscle cramping and injuries associated with being underhydrated.”

See Also Benefits for Creatine For Women

Why You Should Consider Taking It: First and foremost: the endurance factor. Whether you’re a runner, a cardio enthusiast, or a weightlifter, essentially no matter how you perform your workouts, creatine may help you perform those activities longer. “The fact that you will be able to work out at an increased stamina also has impact on maximizing strength gains while preserving existing muscle and also burning more calories and fats during a workout,” says Bazilian. “And creatine has been linked with improved brain function, decreasing risk of age-related loss in muscle and bone mass, and potentially some heart-health benefits.” 

Try: Aim for 2 to 5 grams before a workout or just daily, as Bazilian says timing hasn’t shown to be critically important to its effects. “Taking it with carbohydrates, like fruit or a grain, may help absorption,” she notes. “And when you take creatine, you should also consume plenty of water. Be aware that caffeine may decrease the effect of creatine, so consume separately from your coffee or tea.”

4. L-Arginine

Think of L-Arginine as a means to an end — and that end is to increase nitric oxide levels in the body, which helps dilate the blood vessels to help blood flow to the muscles. It also plays a role in supporting a healthy immune system and helping the liver process metabolic waste.  

Why He Takes It: In a phrase, for the insane muscle pump. Expanding the blood vessels allows for increased blood flow, which means more fluid, oxygen and nutrients are brought to muscle tissue. That creates a temporary “pump,” or swelling of that tissue, which guys seem to like to ogle at in all those mirrors in the gym. “That temporary pump puts pressure on muscle cells that may actually help them grow when they are exercised effectively through training,” says Bazilian. “Men also take L-arginine to potentially help with erectile dysfunction.”

Why You Should Consider Taking It: All that extra blood flow also comes with some potential benefits beyond longer endurance, which in itself can help you achieve your fitness goals. One is lowered blood pressure, but another is that all that extra oxygen flowing to muscle cells increases endurance during workouts. “Some early evidence shows taking arginine might help with weight and waist size in women,” says Bazilian, “and there may be a role with blood sugar control, as nitric oxide, the compound arginine converts to in the body, can stimulate the release of insulin and hormones and compounds in the body.” 

Try: 2 to 6 grams of arginine a day, about 45 minutes before working out. “This can be split into several doses if preferred,” suggests Bazlian. “Some people like taking it before bed, while others like taking it in the morning. While there are no known interactions with foods, be aware that there are some potential drug interactions, including some blood pressure medications, diabetes medications, and medications that slow blood clotting.”

5. Branched-Chain Amino Acids (BCAAs)

It may seem strange to take amino acids by themselves when you’re most likely already eating a protein-rich diet and may also be taking whey protein powder (see No. 1 in this list). BCAAs, which include leucine, isoleucine, and valine, are three of the amino acids that are considered “essential” because the body cannot make them. 

Why He Takes It: BCAAs help build muscle by playing a role in stimulating muscle protein synthesis. Leucine, in particular, is responsible for turning on this muscle protein synthesis pathway, which is the how — along with training — muscle tissue grows.

Why You Should Consider Taking It: In addition to helping maintain your existing muscle tissue and reduce or repair muscle that breaks down with training and synthesizing new muscle tissue, BCAAs are unique supplements among aminos because they can also be used as fuel by muscles. “BCAAs have also been shown to help reduce the muscle soreness after exercise, known as DOMS, as well as decrease exercise-related fatigue, by a sophisticated mechanism that stimulates your brain to make more serotonin,” says Bazilian.

Try: 3 to 6 grams per day, which Bazilian says you can adjust depending on workout frequency and goals. “It can be taken anytime during the day, but there is decent rationale to take it either 45-60 minutes before a workout or within 30-90 minutes post workout during the recovery window where muscle repair, rebuilding and synthesis starts.” 

6. Beta-Alanine

Similar to how arginine creates nitric oxide in the body, beta-alanine helps create carnosine. Because the body can’t create its own supply of beta-alanine, supplementing with it ensures that the body can optimize carnosine production. “Beta-alanine stimulates the muscle cells to make carnosine, which buffers the acid that is produced during hard workouts,” explains Bazilian. “The result is the ability to work harder and longer during intense workouts, allowing for more gains.”

Why He Takes It: Beta-alanine offers the potential promise of increased muscle mass, strength and endurance during workouts that can translate into increased muscle mass. In fact, it’s so powerful that one study even showed that subjects who take the supplement without changing anything about their sedentary ways still gain lean mass. Just think of what it can do when you work out while taking it.” 

See Also Your Muscle-Fatigue Fighter

Why You Should Consider Taking It: Obviously, women benefit from increased muscle mass, strength and endurance, too. “But carnosine — the compound beta-alanine stimulates muscles to produce — has also shown to help delay muscle fatigue and potentially recover faster,” says Bazilian. “This means, not only might you be able to workout longer or with less fatigue, but recover faster and be able to work out stronger again even sooner. That’s a win toward your fitness goals.” And to tip the scales even more in beta-alanine’s favor, one study showed that subjects who took beta-alanine along with creatine reduced more body fat than those who only took creatine. 

Try: 2 to 6 grams total daily, depending on goals, before and after workouts (as a single dose or combination).




Tseh, W., et al. “The Effects of Arginine Alpha-Ketoglutarate Supplementation on Endurance-Trained Females.” Medicine & Science in Sports & Exercise: May 2008, Volume 40, Issue 5, p. S401. 

Smith, A.E., et al. “Effects of beta-alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind trial.” J Int Soc Sports Nutr. 2009 Feb 11;6:5.

Hoffman, J., et al. “Effect of creatine and beta-alanine supplementation on performance and endocrine responses in strength/power athletes.” Int J Sport Nutr Exerc Metab. 2006 Aug;16(4):430-46.

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