Drink milk and grow muscle
Most parents know the importance of providing active teens with proper hydration during and after exercise, but what they may not know is that milk is a great way to do it.
Often overlooked in favour of commercial rehydration drinks, milk contains carbohydrates and electrolytes within a natural food matrix. Milk also has an added benefit because it contains protein too.
But why are proteins and carbohydrates so important? Many athletes include resistance exercise in their training schedules – repeated high-intensity contractions of different muscle groups to build lean body mass. Such intense exercise needs to be supported by a combined protein and carbohydrate intake just before or shortly after exercise to stimulate protein synthesis and muscle growth.
According to Maretha Vermaak, dietitian of the Consumer Education Project of Milk SA, a number of recently published studies have established the positive impact of milk on muscle gain.
“Dairy protein is a complete protein, comprising 80 percent casein and 20 percent whey protein. Whey protein contains a large proportion of branched-chain amino acids, which play an integral role in muscle metabolism and protein synthesis. Research increasingly suggests that consumption of whey protein in particular may:
- stimulate greater muscle protein synthesis than soy protein intake;
- result in greater muscle gain when combined with chronic resistance training;
- and enhance recovery after exercise, especially in younger individuals,” she explains.
The issue of recovery – including rehydration – is particularly important. Research has shown that dehydration impairs performance and has negative health implications, especially in the case of regular and repeated exercise activities. Research also confirmed that electrolytes play a fundamental role in the rehydration process.
“Exercise-induced dehydration, where sweat losses surpass fluid intake, is common among athletes, particularly with prolonged, intense exercise. Low-fat milk has a naturally high concentration of electrolytes that can replace those lost through sweat during exercise,” Vermaak says.
In fact, low-fat milk products came through strongly in the studies as the dairy drink with the potential to have the most positive impact on muscle growth and rehydration when consumed correctly as a post-exercise recovery drink. For example, 300ml of low-fat drinking yoghurt provides more than three times the estimated carbohydrate contribution of full-cream, low-fat and fat-free milk during the post-exercise recovery period. Low-fat flavoured milk was not far behind, at almost double the carbohydrate contribution of these three dairy sources. This compares favourably with popular sports drinks, with milk also being a source of much-needed protein.
“It’s clear from all this research that low-fat dairy drinks provide carbohydrates to help the body refuel; protein to help reduce muscle breakdown and stimulate growth; and fluid and electrolytes to aid in rehydration. Plus that low-fat drinking yoghurt and flavoured milk contribute significantly to the recovery of macro-nutrients in strength training athletes if included in the post-exercise meal,” Vermaak adds further.
It’s recommended that teen athletes consume four servings of dairy per day as part of a healthy, balanced diet that also includes five daily servings of vegetables and fruit. Athletes involved in strength training should aim to consume one gram of carbohydrates per kilogram of body weight and 0.4g protein per kilogram body weight during the first two hours after training.