1. Borg, G. (1998). Barg's Perceived Exertion and Pain Scales. Champaign, TT.; Human Kinetics.
2. Caine, MP. and McConnell, A.K. (1998). Pressure threshold inspiratory muscle training improves submaximal cycling performance. In Proceedings of the Third Annual Conference of the European College of Sport Science (edited by A. Sargeant and H. Siddons), p. 101. Manchester: Centre for Health Care Development.
3. Cohen, J. (1988). Statistical Power Analysis for the Behavioural Sciences. New York: Academic Press.
4. Wetter,T.J. and Dempsey, J.A. (2000). Pulmonary system and endurance exercise. In Endurance in Sport (edited by R.J. Shephard and P.O. Astrand), pp. 52-67. Oxford: Blackwell.