SUMMARY
Penelitian ini bertujuan menghasilkan produk model latihan core stability menggunakan stability ball cabang olahraga renang gaya kupu-kupu usia 9-10 tahun. Penelitian & Pengembangan ini menggunakan pendekatan Borg dan Gall. Subjek yang digunakan 20 atlet untuk uji coba kelompok kecil, 60 atlet untuk uji coba kelompok besar, dan 30 atlet untuk uji efektifitas produk. Model latihan core stability divalidasi ahli kepelatihan kondisi fisik dan ahli olahraga renang. Hasil uji coba kelompok kecil, model latihan core stability mendapat persentase rata-rata 82,20%. Hasil uji coba kelompok besar, model latihan core stability mendapat persentase rata-rata 79,60%. Uji efektivitas produk menggunakan tes kecepatan renang 50 meter gaya kupu-kupu dengan rancangan pretest-posttest control group design. Dari hasil selisih pretest-posttest kelompok eksperimen dan kontrol diperoleh harga thitung = 7,776 dengan signifikansi 0,000. Didapatkan ttabel dari db = 58 dari taraf signifikansi 5% adalah 1,671. Jadi nilai thitung > ttabel (7,776 > 1,671) dan sig. (2 tailed) atau p-value = 0,000 < 0,05. Sehingga disimpulkan terdapat efektifitas hasil kecepatan renang gaya kupu-kupu atlet renang usia 9-10 tahun yang diberikan latihan core stability menggunakan stability ball.Stability Exercise Model In Butterfly Swimming For 9-10 Years Old Children Abstract This research aims to produce the model of core stability training model using stability ball in butterfly swimming for 9-10 years old. This Research & Development uses the Borg and Gall approach. Subjects used 20 athletes for small group trials, 60 athletes for large group trials, and 30 athletes to test product effectiveness. The core stability training model is validated by physical fitness experts and swimming sport experts. Small group trial results, core stability training model got an average percentage of 82.20%. The results of large group trials, core stability training model got an average percentage of 79.60%. Product effectiveness test using 50 meter butterfly swimming speed test with pretest-posttest control group design. From the result of the difference beetwen the pretest-posttest experiment and control group obtained tcount = 7,776 with significance 0,000. Obtained ttable from db = 58 from 5% significance level is 1,671. So tcount> ttable (7,776 > 1.671) and sig. (2 tailed) or p-value = 0.000 < 0.05. So concluded there is effectiveness of swimming pool speed butterfly swimming athletes aged 9-10 years who are given core stability training using stability ball.