Effect of Protein Quality During Overreaching in Trained Cyclists
Condition: Muscle Protein Synthesis
Study type: Interventional

Summary: 
      Athletes frequently undertake periods of intensified training commonly referred to as
      "overreaching." These training periods acutely decrease performance, with the expectation
      that performance will rebound and improve after a short recovery. Yet, overreaching does not
      always improve performance and may be a precursor to overtraining syndrome, a long-term
      decrement in performance. A nutritional intervention focused on the adoption of 'best
      practices' for protein feeding (optimal timing, dose, and quality) could help reduce the
      stress of overreaching, reduce the likelihood of developing overtraining syndrome, and
      augment adaptations to intensified exercise. While the nutrition study is our main interest,
      the investigators first want to validate the measurement of exercise performance.
      Accordingly, this project consists of two related studies: (1) the assessment of short time
      trials for reliability and validity; and (2) the assessment of optimal protein feeding to
      decrease the stress of overreaching and improve outcomes following training.
    

Detailed description: 
      Endurance-trained athletes frequently undergo periods of overreaching (increased training
      loads) to improve performance. In study 1, the investigators will determine whether 4-min and
      20-min time trials are repeatable and whether they (individually or collectively) relate to
      1-hour time trial performance. For Study 2, the investigators propose that proper nutrition
      (with a focus on the dose, timing, and quality of protein) can help mitigate the stress of
      overreaching, which will improve performance. Thus, the investigators will compare the
      effects of two diets that differ in terms of protein servings (dose, timing, quality). In
      Study 2, skeletal muscle biopsies will be collected to determine how dietary protein
      intervention impacts the quality and quantity of skeletal muscle mitochondria in response to
      intense training.

      For study 1, the objective is to determine the reliability and validity of 4-min and 20-min
      time trial performance (mean power output).

      For study 2, the objective is to (1) determine whether following an optimal protein diet
      during a period of intense training will, relative to a typical diet: (1) improve measures of
      exercise performance, (2) improve sleep quality, psychological wellbeing, and immune
      function, (3) improve the quality and quantity of skeletal muscle mitochondria.

      Study 1 is a reliability and validity experiment designed to assess the key outcome measure
      in study 2.

      Study 2 is a randomized, crossover study. Participants will, in a randomized order, complete
      both conditions, separated by a 4-day washout period.
    

Intervention name(s): Alpha-lactalbumin; Collagen peptides
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): A protein fraction of whey protein, higher in tryptophan; Collagen peptides from bovine sources
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Randomized cross-over design
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Other