I am also self conscious about my stomach, but totally get wanting to not feel overheated. I found some open-back tops on Amazon that I really love. The back keeps me cool, but my tummy is still covered. (Bonus if you have a cute, strappy sports bra, it's extra cute) - https://www.amazon.com/dp/B07RX5N56Z/ref=cm_sw_r_apan_glt_i_0WQB8ZJGKDTFSR47VA0C?_encoding=UTF8&psc=1