Electronic Thesis and Dissertation Repository


Doctor of Philosophy




Dr. Peter WR Lemon


Recently, the ingestion of a carbohydrate-protein supplement after exercise has garnered considerable interest among both athletes and scientists. However, debate exists about whether the type of protein consumed, animal vs plant, affects exercise performance differently. Thus, it is the purpose of this dissertation to compare performance outcomes following carbohydrate (CHO)-plant or CHO-animal protein ingestion utilizing a variety of exercise conditions (acute bouts of aerobic exercise, 10 weeks of strength training and six weeks of concurrent training).

Study 1 demonstrated that following a glycogen depleting bout of cycling, dairy chocolate, soy chocolate, hemp chocolate or dairy milk ingestion all enhanced the performance of a subsequent 20km cycling time trial relative to that of a placebo drink (p = 0.02). Further because the drinks were matched for energy and total liquid consumed these data suggest that a post exercise CHO-plant protein drink is as effective as a post exercise CHO-animal protein drink with respect to same day 20km time trial performance following glycogen depleting exercise.

Study 2 demonstrated that regardless of protein type (hemp, dairy milk or whey protein isolate) post training session CHO-protein supplementation increased isokinetic bicep (p =0.03), quadriceps (p =0.04 and isometric bicep strength (p = 0.05) vs a carbohydrate only drink over 10 weeks of strength training. Thus, post training session CHO-protein ingestion appears to be as effective for strength development over 10 weeks of training whether the protein source is vegetable (hemp) or animal (milk, whey).

Study 3 demonstrated that post training session CHO - hemp protein ingestion produced greater improvements in time trial (p = 0.01), peak Wingate power (p = 0.001) and 1-RM strength (p = 0.01) with 6 weeks of concurrent training vs carbohydrate only. Six weeks of concurrent training, when supplemented with hemp based protein-CHO drink post exercise, appears to be effective at enhancing aerobic and anaerobic performance outcomes similarly to what has been previously found with a CHO- animal protein supplement.

Together, these studies demonstrate significant and similar improvements with plant or animal protein-CHO post exercise supplementation for strength or concurrent training and for time trial performance following glycogen depleting exercise.