Elshalakamy, A. ., Shawayka, A. M. (2020). 'The Training Various in two methods Isometric and Isotonic Contraction on respiratory efficiency and some variables of muscle strength and their effect on static exercises in the mandates of the Junior Gymnastics Second Republic Championship to Artistic gymnastics for men under 7 years', The Scientific Journal of Sport Science & Arts, 020(020), pp. 229-252. doi: 10.21608/ijssaa.2020.26764.1043