Should You Drink Milk Post-Workout for Muscle Growth?

glasses of milk

Getty Images / Flavio Coelho

Finding the best protein to build muscle still remains a question for many trying to gain lean mass and lose fat.

The American College of Sports Medicine's recent stand on optimal protein sources indicated milk-based protein is a superior choice.

According to the American College of Sports Medicine, there is strong scientific evidence that “milk-based protein after resistance exercise is effective in increasing muscle strength and favorable changes in body composition.” 

Research has also shown that drinking milk promotes greater lean mass gains and improved strength.

In another study, only the milk-based protein consumers were able to lose fat. It appears nothing fancy or expensive is required to enhance muscle and cut fat but a cold glass of milk.

Why Milk Protein May Be Best

Milk-based or dairy protein appears to be superior largely due to its leucine content along with easily digested and absorbed branched-chain amino acids (BCAAs). Leucine is considered the primary amino acid in the BCAA makeup and responsible for muscle protein synthesis (muscle growth).

Whey protein is also derived from milk and is the byproduct left over from cheese production. Being a milk-based protein, it’s also high in leucine and the common denominator for improved muscle development.

The American Society for Nutrition conducted a study on 48 healthy men over 74 years of age and concluded whey protein effectively stimulated muscle protein.

With age, there is a decline in skeletal muscle. The purpose of the study was to show consuming milk-based protein would stimulate muscle improvement. The findings were supportive of the research and indicated “this effect is attributed to a combination of whey's faster digestion and absorption kinetics and higher leucine content.”

Drinking Milk Found Effective

Medicine and Science in Sports and Exercise examined the effects of fat-free milk consumption on young athletic women. The purpose of the study was to determine if drinking milk after resistance training would increase lean mass and reduce fat. The research lasted for a 12-week period, and the women consumed either fat-free milk or nutrient equivalent carbohydrate. Although lean mass increased in both groups, those who drank milk had greater muscle gains.

Both groups experienced increased in strength, but only women in the milk group experienced fat loss.

Clinical study results showed that milk is “an effective drink to support favorable body composition changes in women with resistance training.” 

Milk Protein Is Better Than Soy

The American Journal of Clinical Nutrition compared drinking fat-free milk to consuming soy protein or nutrient equivalent carbohydrate. The purpose of the research was to prove the long-term effects of different protein sources on muscle growth. The study was conducted on 56 healthy young men who resistance trained 5-days per week. The participants consumed fat-free milk, fat-free soy protein or nutrient equivalent carbohydrate directly after their workouts.

Lean mass gains were made in all groups, but the greatest increases occurred for the men drinking milk only. Greater bone density and fat loss were also better in the milk group.

The study also determined that drinking milk post-workout promotes greater muscle hypertrophy (growth) with resistance training than a soy or nutrient equivalent carbohydrate.

Milk Protein Is Superior

The Journal of Nutrition conducted a study examining the effects of varying levels of dairy, protein, reduced calories and combined with exercise on overall body composition. There were 90 female participants all premenopausal and overweight but otherwise healthy. They were separated into 3 groups and consumed adequate protein and low dairy (APLD), adequate protein and medium dairy (APMD), or high protein and high dairy (HPHD). The liquid dairy protein source was low-fat milk rich in leucine, the main amino acid responsible for muscle growth.

Additionally, the women were required to perform aerobic exercise daily as part of the program and for a 16-week period.

The results suggest that high protein and dairy intake led to the best results in terms of weight loss and muscle gain. 

“We observed what we view as a highly beneficial profile of weight loss in the HPHD group: greater total fat and visceral fat losses, greater lean mass gains, and increases in strength despite identical body weight loss." 

They also contributed the HPHD group outcomes benefited from milk-based protein rich in branch-chained amino acids (BCAAs) leucine, isoleucine, and valine. 

Conclusions and Takeaway

Chronic studies like those above do show consuming milk-based protein after workouts as effective for increasing our muscle, losing fat and gaining strength. The wide variety of research from older men, premenopausal women, young female athletes and resistance-trained men is remarkable. The results all favor one conclusion and support dairy proteins superior to others.

More Research Is Needed

Further research is warranted to examine other high-quality protein sources like eggs, lean meats, and vegetable proteins. It’s important to gather comparable information on how other proteins affect muscle growth, fat loss, and body composition post-workout.

Additionally, it may be recommended to examine active individuals and athletes depending on protein supplementation as a practical way to meet their protein needs.

The science-backed evidence suggests that whole food milk-protein can contribute to significant improvements in muscle growth. Great news for milk drinkers!

5 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance. J Acad Nutr Diet. 2016;116(3):501-528. doi:10.1016/j.jand.2015.12.006

  2. Josse AR, Tang JE, Tarnopolsky MA, Phillips SM. Body composition and strength changes in women with milk and resistance exercise. Med Sci Sports Exerc. 2010;42(6):1122-30. doi:10.3945/ajcn.110.008102

  3. Josse AR, Atkinson SA, Tarnopolsky MA, Phillips SM. Increased consumption of dairy foods and protein during diet- and exercise-induced weight loss promotes fat mass loss and lean mass gain in overweight and obese premenopausal women. The Journal of Nutrition. 2011; 141(9): 1626-1634. doi:10.3945/jn.111.141028

  4. Pennings B, Boirie Y, Senden JM, Gijsen AP, et al. Whey protein stimulates postprandial muscle protein accretion more effectively than do casein and casein hydrolysate in older men. Am J Clin Nutr. 2011; 93(5): 997-10005. doi:10.3945/ajcn.110.008102

  5. Hartman JW, Tang JE, Wilkinson SB, et al. Consumption of fat-free fluid milk after resistance exercise promotes greater lean mass accretion than does consumption of soy or carbohydrate in young, novice, male weightlifters. Am J Clin Nutr. 2007;86(2):373-81. doi:10.1093/ajcn/86.2.373

By Darla Leal
Darla Leal is a Master Fitness Trainer, freelance writer, and the creator of Stay Healthy Fitness, where she embraces a "fit-over-55" lifestyle.