Effects of protein supplementation on IGF-1 and training responses in females

This is a randomised control intervention to assess effects of training with post-exercise protein supplementation on IGF-1. Researchers and Post-graduate students will be supervising the small group training, with initial visits one-on-one, in the School of Physical Education Clinic Gym. Prior to commencement of training 3 separate, pre-training sessions will be conducted for familiarisation and baseline aerobic fitness and lactate threshold, upper body strength and body composition (height. weight. skinfolds girths) measures and to explain diary keeping for diet, exercise and recovery. Two separate appointments will be individually made for baseline blood sampling (day 3-5 menstrual cycle) and DXA scan. Participants will undergo twelve weeks of mixed training, consisting of upper-body resistance training and cycling interval training. Resistance training will be performed twice weekly, with each resistance training session separated by minimally 48 h. Sessions will take~ 45 min. The exercises will include free-weight exercises, targeting the chest, back, shoulders and arms, and abdomen. All exercises will consist of 8 – 12 repetitions, 3 – 4 sets, with 60 – 90 seconds of rest between each set. Load will be increased according to the "rule of two" progression, specifically, if a participant can perform 2 extra repetitions over the assigned number of repetitions across two consecutive sessions, the load will be increased (Baechle & Earle, 2008). The three cycling sessions/week will consist of progressive training on a cycle ergometer, using a square-wave mode of intensity training according to Morio et al (British Journal of Nutrition (1998), 80, 511–519). During the first 2 weeks of training, the training exercise will consist of 20 min at heart rate corresponding to 50% VO2max. Thereafter it will comprise interval-training episodes alternating between heart rate corresponding to 50% VO2max for 5 min and heart rate at lactic threshold for 3 min Intensity and duration of the exercise will gradually increase, with the interval-training episodes alternating between heart rate at lactic threshold to heart rate above lactic threshold during the last 6 weeks. There will also be a 10 min low intensity warm-up and 5 min cool-down, therefore sessions will last ~45 min. An electronic spreadsheet in the clinic will be kept for workoads/ progression and participants will also keep attendance in their daily diary (Wild AI app) as well as other information e.g. other daily exercise, indicators of recovery (resting HR, soreness, energy levels), menstruation, and any other notable (eg illness, pharmaceutical use). Cycling sessions will be separated by minimally 24 h. Resistance and cycling sessions will be separated by minimally 8 h. The first week of training will be 1 to 1 researcher to participant, as will sessions with load increases following 4, 8 week testing. Outside of this will be minimally 1 researcher/assistant to 4 participants. Participants will be randomly assigned to receive either a high (whey) protein (~25 g) or comparator supplement that will be provided after each training session. Both will be mixed with water in a shaker, provided by the researchers, to be consumed immediately after exercise at the clinic. Empty shaker given back to researchers.