The Rock - Solid - Abs Workout - Abs Workout , The plank is one of the best exercises for a flat , toned stomach .
It works all the muscles in your core , including the rectus abdominus Share on Facebook Share on Twitter Share on Google Plus
The Rock - Solid - Abs Workout - Abs Workout , The plank is one of the best exercises for a flat , toned stomach because it works all the muscles in your core , including the rectus abdominus Share on Facebook Share on Twitter Share on Google Plus