Sales of athletic shoes, apparel and gear brand Reebok have more than doubled in the last three years, its sales network has expanded to over 210 stores, after an Aditya Birla group firm acquired its India rights. Aditya Birla Lifestyle Brands Ltd (ABLBL) plans to add 40-50 stores annually over the next few years as it looks to tap significant untapped market opportunities, company officials said in the latest earnings call. Reebok, which delivered around 30 per cent growth in the latest March quarter, continues to witness strong momentum from both same-store sales growth and network expansion, the management said.