HIIT the Core: block 2 workout 4thebalanceguy (59)in Fitness • 2 years ago ▶️ Watch on 3Speak 25 minute interval training workout for stronger abs, a smaller waist, and a healthy lower back. ▶️ 3Speak #health #fitness #abs #cardio #hiitworkout #homeworkout #abworkout #howto #loseweight