P-23  ischemic training gives similar results with classical hypertrophy training in terms of thickness increase and stiffness change of biceps brachii muscle

AimHypertrophy training is a basic training method to increase muscle size, power and endurance for both athletes and non-athletes. Choosing the most timesaving and beneficial training method is always of concern. Classical hypertrophy training consists of concentric and eccentric contractions of subjected muscle with high-loads (75-85% of 1-Repetition Maximum [RM]) usually in 3 sets. Working with such high loads may cause soreness, pain and loss of function in the following days and producing such effort during training is exhausting for most people. Recently, another type of training, ischaemic or occlusion training is becoming more popular. In this type of training, one restricts blood flow at involved extremity from its proximal to the degree that allows arterial flow but decreases/stops venous return, and then trains with lower loads (20-50% of 1-RM). Prior studies showed similar benefits in terms of hypertrophy measured with arm circumference. However, no study investigated how muscle stiffness values change in both groups after hypertrophy training. Therefore we aimed to measure thickness and stiffness changes of biceps brachii muscles after both classical hypertrophy (CH) and ischaemic hypertrophy (IH) training groups using diagnostic ultrasound device.Methods8 healthy volunteers randomised into CH (4) and IH (4) groups. After initial week of familiarisation and baseline measurements conducted in Sports Medicine Department of Istanbul University, participants started 8-weeks training program. Both groups trained with same frequency (3 days a week) but with different intensities. An experienced sports physician recorded thickness measurements using brightness-mode (Image 1) and stiffness measurements using elastography mode (Image 2) of an office type high-equipped ultrasound device before and after the program.ResultsNo statistically significant difference in muscle thickness was observed before and after training periods in both groups (p = 0.068). Hovewer when analysed together (n = 8), there was a significant increase in muscle thickness (p = 0.012). Muscle stiffness did not change significanlty in either group or in total (p = 0.465 for group 1, p = 0.715 for group 2 and p = 0.889 when analysed altogether).ConclusionsBoth groups showed similar thickness increase when measured values (1.7 mm and 1.85 mm) were evaluated. The statistical dilemma showing no increase when groups analysed on their own was attributed to low number of participants. Bic