The Combined Effect of Dairy and Exercise on Bone and Inflammation (Cre-Ex-Inf)

This study analyzes whether dairy supplementation positively impacts loading exercise-induced bone cell activity and inflammation in healthy young females.

Introduction: Two million individuals at a cost of around 2.3 billion dollars a year in Canada suffer from osteoporosis. Research that emphasizes the treatment of this disease is important, but so is research that focuses on prevention; reducing bone loss and/or increasing bone mass when young. In addition, inflammation is an issue as it strongly relates to chronic disease. Countermeasures to improve bone health and inflammation, such as nutrition and exercise, should be explored and implemented. The proposed research combines both nutrition and exercise along with the assessment of bone turnover markers and inflammation in healthy young females, and aims to determine whether dairy versus a carbohydrate-based beverage positively impacts acute bone turnover and the inflammatory response following a bout of resistance and plyometric exercise. Design: Randomized controlled crossover trial. Participants: 13 healthy university aged females. Methods: Participants were asked to complete 2 different acute exercise and nutritional supplement trials. Each trial will be assigned in random order. The two trials were: 1) exercise+carbohydrate (CHO), and 2) exercise+milk (Milk). The whole study, per participant, took a maximum of 8-12 weeks to complete as each supplement trial was separated by ~4 weeks. Each treatment is outlined below. ******DUE TO COVID-19, we removed the treatment trial which involved milk+creatine supplementation. Despite randomization, and before the trial was closed, only 11 participants completed this trial******** Anticipated Results: The investigators anticipate that dairy and exercise will have a greater positive impact on acute bone cell activity and inflammation in healthy young females compared to exercise and CHO.

Participants had a fasted, baseline blood sample (10ml) taken upon arrival to the lab. They then completed a supervised resistance and plyometric exercise bout. Immediately following exercise, 50g of carbohydrate (maltodextrin) + water was consumed. Two more blood samples followed the exercise bout at 5 minutes post (10ml) and 1 hour post (10ml). An additional 50g of carbohydrate was consumed with water 1 hour post exercise. Two more fasting blood samples (10ml) were taken 24 and 48 hours later.

Participants had a fasted, baseline blood sample (10ml) taken upon arrival to the lab. They then completed a supervised resistance and plyometric exercise bout. Immediately following exercise, ~500 ml of skim milk was consumed. Two more blood samples followed the exercise bout at 5 minutes post (10ml) and 1 hour post (10ml). An additional 500 ml of skim milk was consumed 1 hour post exercise. Two more fasting blood samples (10ml) were taken 24 and 48 hours later.

Inclusion Criteria: Female between the ages of 18 and 30 years Normal BMI (18.5-24.9) kg/m2 Low to moderately physically active (0-2 times/week) No allergy to dairy protein or lactose intolerance On no medication related to a chronic condition On birth control (or not but with regular mensural cycle)