Does Dairy Build Muscle Post-Workout?

Lifestyle and niche interest blogs are fun to read (who doesn’t love a good listicle), but they shouldn’t inform your nutrition. 

An article featured in Women’sRunning.com suggested cottage cheese as an optimal post-workout snack – based on a study with shaky findings that only surveyed 20 middle-aged men. 

Even if the research was sound, it’s not fair to apply the conclusion to a female-dominant audience. However, for all the men out there who are considering cottage cheese post-gym, we decided to look into this study to see if it had any merit. Spoiler alert: it doesn’t.

Dairy-Based Funding

The study was conducted in New Zealand and funded several pro-dairy organizations (IE Fronterra – a global dairy nutrition company – and the New Zealand Ministry for Primary Industries). 

The goal was to determine the minimal amount of milk protein to stimulate anabolic signaling in ‘healthy’ middle-aged men post-resistance training.

Study Design

Twenty men between the ages of 38 to 55 were selected for this study. None were on medications or experienced any detectable metabolic, cardiovascular, or neuromuscular conditions. 

Each lived either sedentary or ‘recreational’ lives, and none were currently involved in resistance training. The participants performed four sets of single repetition leg presses and extensions at an 80 percent maximum effort. 

Afterward, they were randomly assigned a formulated milk product fortified with vitamin D and 9 grams of milk protein or a carbohydrate placebo beverage. Muscle biopsy was performed pre-workout and 90-240 minutes post-workout and beverage consumption. This was a double-blind study.

The Results

Ultimately, the researchers were looking at milk protein’s ability to stimulate mTor – a complex that facilitates growth within the body when supplied with nutrients. The issue is, mTor is not only responsible for muscle growth, but for fat storage, immune response, cell progression, and more. 

Researchers often colloquially refer to it as ‘the thing that does everything’. So when the study findings demonstrated that the formulated milk beverage ever-so-slightly stimulated mTor, there can be no way of telling if it led to stimulating muscle growth.

The authors also state: “As little as 9g of high-quality milk protein is able to augment the downstream signaling response induced by resistance exercise in middle-aged men but does not potentiate the increase in amino acid transporter gene expression after resistance exercise.”

Essentially, the results were not statistically significant enough to prove actual muscle growth.

Comparing Milk to Sugar Water (and other flaws)

To be clear, the formulated milk-drinking group showed very few advantages over the placebo group, but even so, the comparison was simply unfair. The ‘isoenergetic carbohydrate placebo’ is technically sugar water, so all the study proved was that post-workout consumption of some sort of protein may be better than drinking pure carbohydrates after a workout. 

We knew that. The danger this study presents is that it can make people believe that dairy-based protein specifically stimulates muscle growth. If researchers were to conduct the same experiment using 9 grams of plant-based protein (IE from soy or pea proteins), they would likely see similar results.

It All Goes Back to the Funding

This was a study funded by the dairy industry to support its sales. No doubt, it accomplished what it set out to do – if Women’s Running is picking up on the vague headline, completely ignoring the design details or the fact that it was based on just 20 middle-aged men, then the researchers obviously made a convincing statement. However, that does not mean it’s valid. 

Science can be manipulated and embellished to favor a hypothesis, and the dairy industry has been employing this tactic for years. 

Knowing that the general public won’t look beyond the conclusion, study designs are manipulated to get the results the industry pays for. Dairy claims are not based in fact – they are based in funding. 

World Plant Milk Day

World Plant Milk Day (WPMD) on August 22 helps people transition away from dairy foods like whey, to healthier plant-based alternatives. Take the 7-day dairy-free challenge starting August 22 and receive free support and tips along the way.

WPMD is running in partnership between Plant Based News and health advocacy organization Switch4Good. The initiative is sponsored by Califia Farms.