Isotonic hamstring training with increased hip flexion - Here is part 3 of the video series showcasing exercises related to addressing folks presenting with proximal hamstring tendinopathy (PHT) ala Tom Goomet al. JOSPT 2016. In this phase, the focus continues to be on building strength and capacity of the hamstring complex with increased hip flexion. Hope this helps you in your clinical endeavors. Aint no thing as magic exercises but rather understanding how to plug them into a program specific to the person in front of you. #simplicityistheultimatesophistication. Special thanks to Nathan Carlson of KC Running Mate for dropping by Metier and doing some camera work! PLEASE SHARE IF YOU FIND THIS HELPFUL.



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You put a lot of effort into your workouts, always looking to perform better and reach your goals.
Chances are you’ve given more thought to your pre-workout meal than your post-workout meal.
But consuming the right nutrients after you exercise is just as important as what you eat before.
Here is a detailed guide to optimal nutrition after workouts.

Eating After a Workout Is Important

To understand how the right foods can help you after exercise, it’s important to understand how your body is affected by physical activity.
When you’re working out, your muscles use up their glycogen stores for fuel. This results in your muscles being partially depleted of glycogen. Some of the proteins in your muscles also get broken down and damaged (12).
After your workout, your body tries to rebuild its glycogen stores and repair and regrow those muscle proteins.
Eating the right nutrients soon after you exercise can help your body get this done faster. It is particularly important to eat carbs and protein after your workout.
Doing this helps your body:
  • Decrease muscle protein breakdown.
  • Increase muscle protein synthesis (growth).
  • Restore glycogen stores.
  • Enhance recovery.
Bottom Line: Getting in the right nutrients after exercise can help you rebuild your muscle proteins and glycogen stores. It also helps stimulate growth of new muscle.

Protein, Carbs and Fat

This section discusses how each macronutrient — protein, carbs and fat — is involved in your body’s post-workout recovery process.

Protein Helps Repair and Build Muscle

Cooked Chicken Breast
As explained above, exercise triggers the breakdown of muscle protein (12).
The rate at which this happens depends on the exercise and your level of training, but even well-trained athletes experience muscle protein breakdown (345).
Consuming an adequate amount of protein after a workout gives your body the amino acids it needs to repair and rebuild these proteins. It also gives you the building blocks required to build new muscle tissue (1678).
It’s recommended that you consume 0.14–0.23 grams of protein per pound of body weight (0.3–0.5 grams/kg) very soon after a workout (1).
Studies have shown that ingesting 20–40 grams of protein seems to maximize the body’s ability to recover after exercise (689).

Carbs Help With Recovery

Young Fit Female Holding a Smoothie in Each Hand
Your body’s glycogen stores are used as fuel during exercise, and consuming carbsafter your workout helps replenish them.
The rate at which your glycogen stores are used depends on the activity. For example, endurance sports cause your body to use more glycogen than resistance training.
For this reason, if you participate in endurance sports (running, swimming, etc.), you might need to consume more carbs than a bodybuilder.
Consuming 0.5–0.7 grams of carbs per pound (1.1–1.5 grams/kg) of body weight within 30 minutes after training results in proper glycogen resynthesis (1).
Furthermore, insulin secretion, which promotes glycogen synthesis, is better stimulated when carbs and protein are consumed at the same time (10111213).
Therefore, consuming both carbs and protein after exercise can maximize protein and glycogen synthesis (1314).
Try consuming the two in a ratio of 3:1 (carbs to protein). For example, 40 grams of protein and 120 grams of carbs (1516).
Eating plenty of carbs to rebuild glycogen stores is most important for people who exercise often, such as twice in the same day. If you have 1 or 2 days to rest between workouts then this becomes less important.

Fat Is Not That Bad

Avocados
Many people think that eating fat after a workout slows down digestion and inhibits the absorption of nutrients.
While fat might slow down the absorption of your post-workout meal, it will not reduce its benefits.
For example, a study showed that whole milk was more effective at promoting muscle growth after a workout than skim milk (17).
Moreover, another study showed that even when ingesting a high-fat meal (45% energy from fat) after working out, muscle glycogen synthesis was not affected (18).
It might be a good idea to limit the amount of fat you eat after exercise, but having some fat in your post-workout meal will not affect your recovery.
Bottom Line: A post-workout meal with both protein and carbs will enhance glycogen storage and muscle protein synthesis. Consuming a ratio of 3:1 (carbs to protein) is a practical way to achieve this.

The Timing of Your Post-Workout Meal Matters

Silver Alarm Clock on a Plate
Your body’s ability to rebuild glycogen and protein is enhanced after you exercise (9).
For this reason, it’s recommended that you consume a combination of carbs and protein as soon as possible after exercising.
Although the timing does not need to be exact, many experts recommend eating your post-workout meal within 45 minutes.
In fact, it’s believed that the delay of carb consumption by as little as two hours after a workout may lead to as much as 50% lower rates of glycogen synthesis (910).
However, if you consumed a meal before exercising, it’s likely that the benefits from that meal still apply after training (91920).
Bottom Line: Eat your post-workout meal within 45 minutes of exercising. However, you can extend this period a little longer, depending on the timing of your pre-workout meal.

Foods to Eat After You Workout

Peanuts, Bananas and a Protein Smoothie
The primary goal of your post-workout meal is to supply your body with the right nutrients for adequate recovery and to maximize the benefits of your workout.
Choosing easily digested foods will promote faster nutrient absorption.
The following lists contain examples of simple and easily digested foods:

Carbs

  • Sweet potatoes
  • Chocolate milk
  • Quinoa
  • Fruits (pineapple, berries, banana, kiwi)
  • Rice cakes
  • Rice
  • Oatmeal
  • Potatoes
  • Pasta
  • Dark, leafy green vegetables

Protein:

  • Animal- or plant-based protein powder
  • Eggs
  • Greek yogurt
  • Cottage cheese
  • Salmon
  • Chicken
  • Protein bar
  • Tuna

Fats:

  • Avocado
  • Nuts
  • Nut butters
  • Trail mix (dried fruits and nuts)

Sample Post-Workout Meals

Combinations of the foods listed above can create great meals that provide you with all the nutrients you need after exercise.
Two Sandwiches with Tuna and Vegetables
Here are a few examples of quick and easy meals to eat after your workout:
  • Grilled chicken with roasted vegetables.
  • Egg omelet with avocado spread on toast.
  • Salmon with sweet potato.
  • Tuna salad sandwich on whole grain bread.
  • Tuna and crackers.
  • Oatmeal, whey protein, banana and almonds.
  • Cottage cheese and fruits.
  • Pita and hummus.
  • Rice crackers and peanut butter.
  • Whole grain toast and almond butter.
  • Cereal and skim milk.
  • Greek yogurt, berries and granola.
  • Protein shake and banana.
  • Quinoa bowl with berries and pecans.
  • Multi-grain bread and raw peanuts.

Make Sure to Drink Plenty of Water

Blue Bottle of Water
It is important to drink plenty of water before and after your workout.
When you are properly hydrated, this ensures the optimal internal environment for your body to maximize results.
During exercise, you lose water and electrolytes through sweat. Replenishing these after a workout can help with recovery and performance (21).
It’s especially important to replenish fluids if your next exercise session is within 12 hours.
Depending on the intensity of your workout, water or an electrolyte drink are recommended to replenish fluid losses.
Bottom Line: It is important to get water and electrolytes after exercise to replace what was lost during your workout.

Putting It All Together

Consuming a proper amount of carbs and protein after exercise is essential.
It will stimulate muscle protein synthesis, improve recovery and enhance performance during your next workout.
If you’re not able to eat within 45 minutes of working out, it’s important to not go much longer than 2 hours before eating a meal.
Finally, replenishing lost water and electrolytes can complete the picture and help you maximize the benefits of your workout.
Chris Johnson demonstrates several exercises for proximal hamstring tendinopathy based off of a recent paper by Goom et al.

Isomtric Hamstring Loading

Calorie density is used to describe the number of calories in a given volume or weight of food.
Understanding how it works can help you lose weight and improve your diet (1).
What’s more, focusing on low-calorie-dense foods allows you to eat a large volume of food while still cutting back on calories (234).
This can have many health benefits, including an increased nutrient intake and weight loss.
This article explains everything you need to know about calorie density.

What Is Calorie Density?

Calorie density is a measure of the calorie content of food relative to its weight or volume.
It is also called energy density, and is usually measured as calories per 100 grams (3.5 ounces) of food.
Choosing foods with a low calorie density can help with weight loss. It makes you automatically eat fewer calories while still eating large and filling portions (56).
An easier way to make sense of this is to imagine a full plate of food. The fewer calories the plate contains, the lower the calorie density of the meal is.
A vegetable that contains 30 calories per 100 grams has a low calorie density, while chocolate that contains 550 calories per 100 grams has a very high calorie density.
This diagram shows the concept very well:
Calorie Density Concept Diagram
Although calorie density may be less well known than other weight management methods, such as calorie counting, choosing foods based on this measure may actually be simpler and more effective (7).
For example, basing your diet on low-calorie-dense foods tends to reduce your food options in a positive manner because it limits you to predominantly healthy and nutrient-rich whole foods.
It can quickly clean up your diet, eliminating most calorie-dense, processed foods that are generally unhealthy and easy to overeat.
Summary: Calorie density describes the number of calories per weight or volume of food. It’s a very simple, effective method to improve your diet.

How Does Calorie Density Affect Weight?

Carrot, Bell Pepper Slices and Celery in a Glass on Scales
Eating too many calories is a key factor in weight gain (89).
Several studies have shown that individuals who consume low-calorie-dense diets also consume fewer total calories per day. This is also linked with a lower body weight, body mass index (BMI) and waist circumference (1011).
Accordingly, studies have shown that those who consume diets made up of high-calorie-dense foods have an increased risk of weight gain and obesity (1112).
Calorie density also has important effects on hunger.
Low-calorie-dense foods tend to contain more water and fiber, along with less fat. This is great for making you feel full and reducing daily calorie consumption (13).
In contrast, many high-calorie-dense foods are highly processed and extremely palatable. As you may know, they are very easy to overeat.
Research shows that natural, whole foods help signal your brain to stop eating, while this effect is delayed when you eat highly processed foods (1415).
In one study, participants ate 56% more calories when provided with a high-energy-dense meal, compared to a low-energy-dense meal (2).
Another study compared calorie intake for high- and low-calorie-density meals that were matched for palatability and macronutrients.
Participants given the high-calorie-dense meal consumed an average of 425 more calories than when they were given the low-calorie-dense meal (3).
Summary: Research has linked people’s intake of high-calorie-dense foods with weight gain and obesity. Those who eat more low-calorie-dense foods tend to eat fewer calories and have a lower body weight.

A Low-Calorie-Dense Diet Helps You Lose Weight

Apples, Grapes, a Fork and a Knife on Scales
A low-calorie-dense diet is perfect for weight loss for several reasons.
For starters, it focuses on natural, whole foods and limits your intake of processed foods.
This is normally combined with an increased intake of protein, vegetables and fruit.
All of these have been shown to aid weight loss by reducing total calorie intake per meal or per day (1617).
A low-calorie-dense diet can help with hunger, since your stomach senses the volume of food you have consumed in a meal.
A low-calorie-dense meal also fills your plate. This helps make your meal last longer and forces you to chew more, further increasing your feelings of fullness (13).
In one study, participants lost an average of 17 lbs (7.7 kg) after they switched their high-calorie-dense fats to low-calorie-dense fruits and vegetables for one year (4).
Another study found that participants significantly reduced their chance of weight gain and obesity simply by replacing high-calorie-dense snacks with low-calorie-dense snacks (18).
Finally, results from a five-year observational study found that men and women who consumed lower-calorie-dense diets had significantly lower measurements of waist circumference and BMI (10).
Summary: Research has shown that a low-calorie-dense diet can be a great method to lose weight and improve your general eating habits.

A Low-Calorie-Dense Diet May Improve Health

Plate of Fish, Potatoes and Broccoli
Quite simply, a low-calorie-dense diet forces you to overhaul your diet and make many positive changes.
All of these changes benefit your long-term health.
A low-calorie-dense diet includes:
  • Less processed food: Your intake of processed, unhealthy food will be reduced.
  • More healthy food: You will eat more low-calorie, highly nutritious foods.
  • More lean proteins: These can help with weight loss and have several other benefits (16).
  • More nutrients: A low-calorie-dense diet encourages you to consume more micronutrient- and antioxidant-rich fruits and vegetables (19).
  • Reduced calorie intake: Reducing your calorie intake and losing weight is one of the best ways to improve your health if you’re overweight (2021).
  • A well-balanced, sustainable diet: This way of eating teaches you to focus on healthier, low-calorie foods while not forcing you to totally eliminate other foods or food groups forever.
Summary: Along with helping you lose weight, a low-calorie-dense diet is also linked with many other aspects of a healthy lifestyle.

Foods That Have a Low Calorie Density

Oranges on a Scale and in a Basket
Apart from healthy high-fat foods, such as nuts and olive oil, most natural foods have a very low calorie density. These include:
  • Vegetables: Vegetables have a very low calorie density. Most green vegetables have the lowest out of all foods. This is because they are primarily made up of water, fiber and a very small amount of carbs.
  • Meat and fish: Lean proteins like chicken, white fish and turkey have a low calorie density, yet fattier meats and fish have moderate-to-high calorie density.
  • Fruits: These have a low calorie density because of their high fiber and water content. Berries and other watery fruits tend to have the lowest density.
  • Milk and yogurt: Reduced-fat milk and yogurts with no added sugar also have a low calorie density and provide a good source of protein.
  • Eggs: Whole eggs are a protein-packed superfood with a low calorie density, especially when combined with vegetables into meals such as omelets.
  • Starchy carbs: Some natural starchy carbs like potatoes, legumes and other root vegetables can have a low-to-moderate calorie density. This is especially true once they’re cooked, since they fill with water.
  • Sugar-free drinks: Beverages such as water, coffee, tea and other sugar-free drinks technically have a low calorie density and can help keep you full.
Summary: Most unprocessed and natural foods have a low calorie density. This is particularly true of vegetables, fruits, lean meats and fish and eggs.

Highly Calorie-Dense Foods to Limit

Chocolate Chip Cookies
If you want to try this approach and base your food selection on calorie density, you will need to limit your intake of foods with high calorie density.
Here are a few key foods you’ll want to limit:
  • Candy and chips: Candy and chips tend to be high in sugar and fat, making them very calorie-dense and very easy to overeat.
  • Pastries and cakes: Like candy, pastries and cakes are very calorie-dense and easy to overeat.
  • Fast foods: These are some of the most calorie-dense food on the planet. Studies show an average fast food meal contains around twice the calories of a normal, healthy meal (5).
  • Oils: While certain oils are healthy, such as coconut and olive oil, they still have a very high calorie density. Avoid all processed vegetable oils and consume healthy oils in moderation.
  • High-fat dairy: Although they may have health benefits, foods like butter, cream and cheese have very high calorie densities. Consume them in moderation.
  • Fatty meats: Some fatty meats have a very high energy density. This includes bacon, sausages, lamb, fatty beef cuts and several others.
  • Nuts: Like other healthy fat sources, nuts are very calorie-dense. While they do have many health benefits, they are easy to overeat. Try measuring out your portions before you eat them.
  • High-fat condiments: Some sauces and sides, such as mayonnaise, pesto and ranch dressing, are very high in calories and should mostly be avoided.
  • Sugary drinks: Soda, juice, commercial high-sugar smoothies and milkshakes are high in empty calories and should be avoided as much as possible.
Summary: If you are trying to lose weight, limit your intake of most foods with high calorie density. Some natural high-fat foods are healthy and can be consumed in small quantities.

The Bottom Line

Out of the hundreds of diets around, an eating plan based on foods with a low calorie density is probably one of the most sensible and effective. It’s also very easy to understand and implement.
Unlike diets that focus on excluding food groups, a low-calorie-dense diet allows you to consume all foods while simply shifting your focus towards healthy, whole foods.
Plus, you’ll also have less hunger and able consume a large amount of healthy, whole foods.
By basing 90% of your intake on foods with a low calorie density, you can easily reduce calorie intake and lose weight with little effort.

Testosterone is the key male sex hormone, but is also important for women.
It plays a crucial role in muscle growth, fat loss, and optimal health (1).
However, testosterone levels in men are now lower than ever, partly caused by the unhealthy modern-day lifestyle (23).
Testosterone boosters are natural supplements that can increase your testosterone levels.
They work by directly increasing testosterone or related hormones, but some work by preventing testosterone from being converted into estrogen.
Many of these boosters have been scientifically verified in human studies.
Here are the eight best testosterone boosting supplements.

1. D-Aspartic Acid

D-Aspartic acid is a natural amino acid that can boost low testosterone levels.
Research suggests that the primary way it works is by increasing follicle-stimulating hormone and luteinizing hormone (4).
This is important, because luteinizing hormone makes the Leydig cells in the testes produce more testosterone.
Initial research in animals and humans has found that as little as 12 days of D-aspartic acid seems to increase luteinizing hormone as well as testosterone production and transportation around the body (4).
It may also aid in sperm quality and production. One 90-day study gave D-aspartic acid to men with impaired sperm production. Sperm count doubled, rising from 8.2 million sperm per ml to 16.5 million sperm per ml (5).
In another study, athletic men with healthy testosterone levels followed a 28-day weight-lifting routine. Half of them were given 3 grams of D-aspartic acid per day.
Both groups showed significantly increased strength and muscle mass. However, there was no increase in testosterone in the D-aspartic acid group (6).
Taken together, these findings suggest that taking D-aspartic acid may be most beneficial in people with low testosterone or in those with impaired sexual function, but not necessarily in individuals with normal testosterone levels.
Bottom Line: D-Aspartic acid may work by stimulating some key testosterone-producing hormones. Doses of 2–3 grams seem to be effective for those who are testosterone deficient.

2. Vitamin D

Bottle of Vitamin D Capsules
Vitamin D is a fat-soluble vitamin produced in the skin when exposed to sunlight.
Its active form functions as a steroid hormone in the body.
Nowadays, a large portion of the population has very little exposure to sunlight, resulting in low or deficient levels of vitamin D (7).
Increasing your vitamin D stores may boost testosterone and improve other related health measures, such as sperm quality (8).
One study found a close correlation between vitamin D deficiency and low testosterone. When participants spent more time in the summer sun and their vitamin D levels increased, so did their testosterone levels (8).
In a year-long study, 65 men were split into 2 groups. Half of them took 3,300 IU of vitamin D every day. The supplement group’s vitamin D levels doubled and their testosterone levels increased by around 20%, from 10.7 nmol/l to 13.4 nmol/l (9).
To get more vitamin D, increase your sun exposure. You can also take around 3,000 IU of vitamin D3 daily and eat more vitamin-D-rich foods.
Bottom Line: Vitamin D is an important vitamin that may boost testosterone levels, especially if your vitamin D levels are deficient.

3. Tribulus Terrestris

Young Man with a Pill and a Glass of Water in Hand
Tribulus (Tribulus terrestris) is an herb that has been used for centuries in herbal medicine.
Most of the current research on it consists of animal studies, which show improved sex drive and increased testosterone levels.
One 90-day study in men with erectile dysfunction found that taking tribulus improved self-reported ratings of sexual health and increased testosterone levels by 16% (10).
However, the current research has shown no benefit of taking tribulus for young elite athletes and healthy individuals with normal testosterone levels (11).
As with most other testosterone boosters, it appears tribulus has benefits in those with low testosterone or impaired sexual function, but does not appear to increase testosterone in individuals with normal or healthy levels.
Bottom Line: Tribulus may help with sex drive and improve sperm health, as well as increase testosterone in men with impaired sexual function.

4. Fenugreek

Open Green Bottle Filled with Capsules
Fenugreek is another popular herb-based testosterone booster.
Some research suggests it may work by reducing the enzymes that convert testosterone into estrogen.
One of the most comprehensive studies tested two groups of 15 college men over an eight-week period.
All 30 participants performed resistance training four times a week, but only the participants in one of the groups received 500 mg of fenugreek per day.
Both free and total testosterone levels increased in the fenugreek group, whereas the group that only weight trained actually experienced a slight decline. Those who took fenugreek also experienced a greater increase in fat loss and strength (12).
Another study examined how fenugreek affects sexual function and quality of life.
The researchers provided 60 healthy men between 25 and 52 years old with either 600 mg of fenugreek or an empty placebo pill every day for six weeks (13).
The participants reported improvements in strength after taking the fenugreek supplements. The researchers also found:
  • Increased libido: 81% of the group.
  • Improved sexual performance: 66% of the group.
  • Greater energy levels: 81% of the group.
  • Improved well-being: 55% of the group.
Bottom Line: 500 mg of fenugreek per day seems effective for boosting testosterone levels and sexual function in both deficient and healthy men.

5. Ginger

Yellow Pills Spilling out of a Bottle
Ginger is a common household spice that has played a role in alternative medicine for centuries.
It has many health benefits, with strong research showing it may reduce inflammation and maybe even boost testosterone levels (14).
Several studies in rats have found ginger has positive effects on testosterone levels and sexual function. In one 30-day study, researchers found ginger increased testosterone and luteinizing hormone in diabetic rats (15).
In another study, the rats’ testosterone levels nearly doubled. A third study found greater increases in testosterone when they doubled the amount of ginger they gave the rats (1617).
In one of the few human studies, 75 infertile men were given a daily ginger supplement. After three months, they had experienced a 17% increase in testosterone levels and their levels of luteinizing hormone had nearly doubled (18).
When measuring sperm health, the researchers found several improvements, including a 16% increase in sperm count (18).
Although it is still early days in the research on ginger and testosterone, eating ginger is very safe and provides numerous other health benefits.
Bottom Line: Ginger may increase testosterone levels and sperm count in infertile men. Effects on healthy humans need to be studied.

6. DHEA

Two Pill Bottles
Dehydroepiandrosterone (DHEA) is a naturally occurring hormone within the body.
It plays a role in boosting testosterone and controlling estrogen levels. Based on its biological effects, DHEA has become an extremely popular way to boost testosterone.
Out of all the testosterone boosting supplements, DHEA has the best and most extensive research behind it.
Several studies have found that 50-100 mg of DHEA per day can boost testosterone levels by up to 20% when compared to a placebo (192021).
However, as with most supplements, the results are mixed. Several other studies used similar dosing protocols and found no effect (222324).
For this reason, the effects of DHEA on testosterone levels aren’t clear. Nevertheless, DHEA use is banned in professional sports and therefore not suitable for competitive athletes (25).
As with some of the other supplements, it may benefit those with low DHEA or testosterone levels.
Bottom Line: Although DHEA is one of the most popular testosterone boosters on the market, the research is still mixed. Around 100 mg seems to be a safe and effective daily dose.

7. Zinc

Male Hands Holding Pills and a Pill Bottle
Known as an aphrodisiac, zinc is an essential mineral involved in more than 100 chemical processes within the body.
As with vitamin D, zinc levels within the body have been closely associated with testosterone levels (26).
One study that measured this association found that restricting zinc intake from foods lowered testosterone levels in healthy men. As expected, zinc supplements in zinc deficient men also increased testosterone levels (26).
Another study measured the effects of zinc on infertile men with either low or normal testosterone levels.
The researchers found significant benefits for those with low levels, including increased testosterone and sperm count. However, they found no additional benefit for men with normal levels (27).
In elite wrestlers, taking zinc each day also helped reduce a decline in testosterone levels following a 4-week high-intensity training regimen (28).
In light of these studies, zinc may help boost testosterone levels if you have low testosterone or are deficient in zinc. Taking zinc also appears to be helpful if you struggle to recover from high-intensity exercise (2930).
Bottom Line: Taking zinc may be effective in those with low zinc or testosterone levels, or those who are currently in stressful training.

8. Ashwagandha

Bottle of Herb Capsules
Also known as Withania somniferaashwagandhais another herb used in ancient Indian medicine (31).
Ashwagandha is primarily used as an adaptogen, meaning it helps your body handle stress and anxiety (32).
One study tested its benefits on sperm quality in infertile men, who received 5 grams per day over a three-month period.
The men in this study had a 10-22% increase in testosterone levels. In addition, the partners of 14% of participants became pregnant (33).
Another study suggests ashwagandha increases exercise performance, strength and fat loss, while also boosting testosterone levels significantly (34).
At present, it seems likely that ashwagandha could help increase testosterone levels in stressed individuals, possibly by reducing the stress hormone cortisol.
Bottom Line: New research shows ashwagandha may help increase testosterone levels, sexual function and body composition.

Healthy Testosterone Levels Are Crucial

Testosterone is absolutely crucial for many aspects of health and body composition.
Interestingly, hundreds of testosterone-boosting supplements are now available. However, only a few have significant research behind them.
Most of these supplements will likely only cause noticeable benefits in individuals with fertility issues or low testosterone levels.
Some also appear to benefit competitive athletes or dieters, who often experience significant decreases in testosterone due to a restrictive or stressful regimen (35).
Many of them may also work for healthy and active individuals (such as weight lifters), but this hasn’t been studied properly in most cases.