To improve the effect and the safety of Kaatsu training, A training system includes a tight fitting device which is intended to be placed around a compressed range of an arm or a leg and which has a pneumatic bag, and a training device adapted to control the compression pressure that is applied to a compressed range by the tight fitting device by means of supplying air to the pneumatic bag of the tight fitting device or removing the air from the pneumatic bag. The training device supplies the air to the pneumatic bag and removes the air from the pneumatic bag in such a manner that the compression pressure that is applied by the tight fitting device to the compressed range oscillates between an upper peak and a lower peak within a range lower than an appropriate pressure.