Pushing up of the body is a key developmental milestone for babies. It marks the ability of your newborn to lift its head up properly, take the weight of the torso on his two hands and be able to support the weight of its upper body, while lying on the stomach.
Babies develop strength and coordination by raising their heads up from a flat surface at about 2 months, then by leaning on their forearms at about 3 months and finally by pushing up on just their hands at about 4 to 5 months.
The first attempts would only be half successful. Only by 6 months, the baby should be able to lift the upper body by balancing the weight on its hands.
Tummy-time is essential for bringing about this development. Making your baby lie down on his/her stomach on a flat surface would make him/her to lift his/her head to see what is around. The baby would exert small amounts of pressure on the surface beneath him/her and try popping up his/her body by bearing weight on his/her arms, palm, fingers, and legs.
It has been observed that 6-month-old babies who were made to lie on their backs most of the time had less advanced motor skills when it came to creeping and pushing up, than those who were made to lie on their stomachs for some time every day.
Observe a strict tummy-time schedule. Be sure to give your baby plenty of short stretches of tummy time; do not fall into the trap of keeping her in your arms too much. Spend fifteen or twenty minutes per sitting, and do it with your child around three to four times in a day.
Keep in mind that building muscles necessary to master this milestone take a lot of work, considering how heavy her head is compared to the rest of her body. So you need to keep an eye out to make sure he/she is not getting stressed, tired, or end up injuring himself/herself.