I am a personal trainer (BS in Exercise Physiology) and yes, if you are pushing 3 kiddos in a stroller and doing 3mi in 30-min pat yourself on the back, that is excellent! You can tell if you are working hard enough by doing the talk test, if you can say 3-5 words in a sentence, you are working out hard enough, if you can only say 1-2, you are working too hard, anything more than 5 words you need to kick it up.
Keep up the good work!
J. W. MPH, ACE-CPT
Wellness Educator in Maternal and Child Health
Master Trainer for Healthy Moms Fitness