Rethinking Tummy Time

Helping Children Thrive by Expanding Prone Time Possibilities

Babies need to spend adequate time on their bellies to develop fully. Though most agree with this statement, babies today may not be receiving nearly enough time in prone to develop optimally. How much time should infants be on their bellies?

There is no easy answer to this question, and it varies depending on who you ask. However, by exploring more about prone positioning—also called “tummy time”—we can gain a wider perspective about:

• Why time on the belly is crucial to infant development
• What can happen if time on the belly is lacking
• What we can do if sufficient prone time was missed in infancy

Many parents are dismayed because they know about the importance of tummy time, but their babies protest when placed in prone. Babies who dislike being in prone are most likely uncomfortable because they do not have the core muscle strength that would allow them to easily maintain this position. When babies spend sufficient time in prone from birth onward it naturally develops the core strength needed for comfortable, sustained tummy time. If time in prone is insufficient from the beginning of life, babies are more likely to cry when put on their bellies later on.

Here we discuss activities to promote a child’s ability to be in prone in ways that are comfortable and strength-building. We will also discuss one technique I have recommended in the past—but now know it should only be used very sparingly. I will share what this technique is and why to use caution—plus what we can do instead to promote prone time. You will see an amazing 21 second video of an 8-week-old infant who had been sleeping mostly in prone since she was a week old. Watching this video in slow motion gives us an awe-inspring look at the wonders of development.

Tummy Time or Belly-to-Earth? Beyond Supervised Tummy Time

We often think of a baby being prone on a floor or in a bed. However, being prone also happens while the baby is being held and snuggled against the body of a caregiver. For example when a parent is upright or reclining with the infant resting on the parent’s chest, this is a “belly-to-earth” position. The phrase “belly-to-earth” was coined by Kathleen Porter, author of Healthy Posture for Babies and Children, as a way to distinguish prone time as wholly natural for babies as opposed to just supervised “tummy time” that is very limited in scope (Porter, 2017).

To understand this further, Porter points out that all primates instinctively hold their babies with bellies facing the mother’s chest (Porter, 2017). Just after a human baby is born, our clear instinctive response is to place the baby belly-down on the mother’s body (with mother as “Earth”—the baby’s first landing spot after emerging from the watery womb). This belly-to-belly positioning allows a healthy, unmedicated newborn to engage in the breast crawl and initiate the first feeding. The breast crawl would not be possible if babies were placed on their backs, in supine position. In prone position, it is the pushing off with the limbs that allows the infant to lift the head and propel forward to find the breast. Being in supine position is physically disempowering for newborn infants because they cannot use their limbs to push down into the surface. The actions of lifting the head and propelling forward are unavailable to a newborn infant placed on the back. Beyond the moment of birth and the initial breast crawl, the most natural, protective, and nurturing place for a newborn baby is belly-down in the arms of caregivers. At the beginning of life, babies naturally bond with and cling to their mothers and fathers. Experiencing the parents’ nurturing embrace is part of what helps the infant to integrate the Moro reflex. These first loving and soothing embraces are ideally carried through a lifetime of emotionally secure feelings and hugs with family members, friends, and loved ones.

Physical Empowerment in Prone Position

When we think of the breast crawl and the Moro embrace, we see the necessity of prone positioning for a newborn’s on-the-belly engagement and development. Beyond the newborn stage, prone positioning continues to be beneficial for a growing infant. Mothers throughout the ages have noticed their babies sleep more deeply and peacefully in the prone position and they were happy when awake in prone “…we remember our babies sleeping more soundly on their bellies, without a need to be swaddled to feel physically secure…When awake, they busied themselves wiggling around at the earliest age, and as they grew in strength and dexterity, they kicked and pushed off with their legs and squealed with delight as they taught themselves new tricks” (Porter, 2017, p. 73). This wiggling around in prone includes movements of the head, trunk, arms, and legs—adding up to hundreds of little movements a day that help a growing baby to develop more strength with each passing hour in prone. You can see a delightful video example of this in an 8-week-old infant who had been sleeping in prone from the time she was one week old. Look at this short video in slow motion—it is astounding to see all of the movements this baby does in only 21 seconds! Significant effort is required to make all of these involuntary, instinctive movements. But the efforts a baby makes in prone are exactly what is needed to build core strength and provide the fuel for maturing the brain, body, and neuro-sensory-motor systems.

What About Safe Sleep and SIDS?

Prior to the “Back to Sleep” campaign that began in 1994 in the USA (now called “Safe to Sleep”), newborn infants might spend approximately 16 hours a day in prone position—combining awake and asleep times (Porter, 2017, p. 70). The reason for the Safe to Sleep campaign was to prevent sudden infant death syndrome (SIDS). However, some argue that there may be other factors which are far more likely to contribute to SIDS than prone sleeping. For a thorough look into the issue of SIDS, and a beautifully illustrated analysis about why time in prone is essential for a baby’s full development, read the excellent book by Kathleen Porter: Healthy Posture for Babies and Children (Porter, 2017).

Babies in prone position seem to sleep better than babies in supine position. In 1993 researchers studied the sleep of healthy infants at 3 months of age. In contrast to supine sleepers, babies sleeping in prone position slept for longer durations. The babies sleeping on their bellies had less arousals, and when they did wake from sleep, the duration of the arousals were significantly less than for the babies who slept on their backs (Kahn et al., 1993). Perhaps this is why researchers also found that healthy babies themselves tend to prefer sleeping in prone rather than in supine position (Togari et al., 2000). Other researchers found that prone sleeping in healthy infants was associated with better gross motor development. They also found that babies who slept on their bellies were more able to lift and turn their heads away from blankets that might restrict their breathing (Paluszynska et al., 2004).

Physical Disempowerment in Supine Position—A Problem with Devastating Consequences

For a growing infant, excessive time in supine positioning is physically disempowering. According to Porter (2017), a lack of time in prone position in early infancy likely contributes to the following challenges:

• Lack of core strength
• Poor posture—lack of natural body alignment
• Poor balance
• Poor development of the enteric nervous system
• Poor head control
• Poor sleep patterns
• Misaligned postural and movement patterns leading to pain later on in childhood
• Inability to complete primitive reflex integration

Any of these challenges could be very detrimental to an infant’s future development and well-being. Each of these challenges signal poor sensory processing development, and could contribute to neurodevelopmental disabilities such as ADHD or autism.

In the United States more than 1 in 6 children suffer with a neurodevelopmental disability—and prevalence rates are rising (Zablotsky et al., 2019). Time in prone is necessary for many developmental processes—including the development of core strength, head control, and postural control—all of which are important for sensory development. So it makes sense that a lack of time on the belly in infancy may contribute to sensory disorders and neurodevelopmental disorders. In one of many research examples, poor postural control was so strongly associated with ADHD and autism that researchers concluded poor postural control would be a useful biomarker in the risk assessment for neurodevelopmental disorders (Zoccante et al., 2021).

Positional Skull Deformities

Excess time in supine positioning is also associated with positional skull deformities (plagiocephaly and brachycephaly). Skull deformities such as flattened or misshaped heads can be mild to severe and are thought to occur in part due to an infant being in the same position, usually supine, for too long (Porter, 2017). While several factors could be involved, supine sleep position is considered a primary risk factor for developing skull deformities (Ballardini et al., 2018). Rates of skull deformities in early infancy are alarming. For example, Ballardini et al., found that 37.8% of healthy, full-term infants between the ages of 8 and 12 weeks had positional plagiocephaly (2018) and Mawii et al., found 46.6% of infants between the ages of 7 and 12 weeks had developed positional plagiocephaly (2013).

What are the long-term consequences of positional skull deformities?

We may not ever fully know all of the long-term consequences of positional skull deformities in infants, and mild skull deformities in babies may resolve over time on their own. However, researchers found that having moderate to severe positional plagiocephaly or brachycephaly in infancy was later associated with lower scores on cognitive ability and academic achievement tests in school age children. In contrast, a control group of children with no history of positional skull deformities in infancy had higher scores in tests of cognitive ability and academic achievement (Collett et al., 2019).

What sleep position is best to prevent skull deformities?

Researchers have found that the likelihood of developing positional plagiocephaly is three times greater for infants who sleep on their backs than for infants who are prone sleepers (Ballardini et al., 2018). Conversely, contrasted with supine sleepers, prone sleeping infants were seven times less likely to develop positional plagiocephaly (Ballardini et al., 2018).

Belly-to-Earth for Optimal Development—4 Examples

Given all of the challenges that can happen when babies miss time in prone, it is good to dive deeper into why prone time is so important. We know that babies require stimulation to grow and develop. Rich sensory experiences, especially in early infancy, are crucial for brain and body development. With the necessity for sensory-rich experiences in mind, the four examples here show why spending ample time in belly-to-earth position helps infants develop optimally:

Example 1. Whether awake or asleep, healthy newborn babies lying in prone will move and frequently adjust their positioning. These adjustments include periodically lifting and turning the head to one side or the other. This is the beginning of core strength and head control, which are vitally important for proper sensory, motor, and speech development. A newborn baby in supine position can turn the head side-to-side, but cannot yet lift the head against gravity. The opportunities to build core and neck strength for head control are missed in this disempowering supine position. A prone infant can develop head control far more effectively than a baby who is in supine position.

Example 2. Another big part of development that babies miss when placed on their backs is the ability to push off of a surface with arms, hands, legs, and feet. Pushing against a surface provides input to the baby via ground reaction force (GRF). GRF is a basic concept in physics: Put simply, GRF travels from the surface back into the baby’s body and provides immediate sensory information and feedback while building strength in the core and limbs. The GRF from pushing off with the trunk and limbs in prone gives the brain and sensory systems enormous amounts of sensory feedback, which is crucial for fueling an infant’s growth and maturity.

When a baby is placed belly-to-earth, she also receives rich sensory input because of the immense quantity of nerve endings that are stimulated, especially in the hands and feet. The stimulation of the hands and feet catalyzes the growth of the nervous and sensory systems and supports the attainment of developmental milestones. In contrast, when a baby is placed on the back there is very little tangible surface for arms, legs, hands and feet to push against or to feel unless the baby is in exagerated extension, an unnatural position for an infant. The infant who is primarily in supine misses this sensory input, which equates to many lost opportunities for brain and body development.

Example 3. When we lie in prone position and pay attention to our physical sensations for a while, we can notice the tactile feedback provided through our bellies as we breathe. In prone we can feel our abdomen expanding rhythmically as we breathe. A prone baby receives this dynamic, rhythmic-tactile stimulation with each breath. A baby simply cannot get this same rhythmic-tactile belly breathing stimulation when placed on the back—it is impossible because our bellies expand forward (anteriorly) when we breathe. Since each breath in prone is an opportunity for tactile and rhythmic stimulation we can see why, over time, a baby who spends many hours on the back faces a huge loss in the sensory input required for optimal development.

A lack of rhythmic input in infancy could also contribute to arrhythmia—the inability to produce a smooth rhythmic motor pattern. Arrhythmia is a common feature of the following neurodevelopmental disorders:

• Autism (Lense et al., 2021)
• Speech and language disorders (Lense et al., 2021; Ladányi et al., 2020)
• Developmental coordination disorder (Lense et al., 2021; Ladányi et al., 2020)
• ADHD symptoms (Lense et al., 2021; Ladányi et al., 2020)
• Dyslexia (Ladányi et al., 2020)

Example 4. Prone positioning is also important for reflex integration and for meeting milestones like rolling over, belly crawling, and hands-and-knees crawling. Crawling reflexes, and crawling itself, are important for development and these also rely on prone positioning. This is because time spent in belly-to-earth is vital for a baby to be able to practice all of the reflex patterns and precursor movements required to accomplish important milestones like crawling. When a baby is placed in supine position, he has little opportunity practice the precursor movements needed for crawling and other milestones. Read about the importance of crawling and what to do if the crawling milestone was not met infancy.

What can we do if prone time was missed in infancy?

If a child did not get enough time in prone during infancy, what can we do to make up for lost development? Fortunately, there are many games and playful activities we can do to engage children while they are on their bellies. Rolling a ball to each other while prone, or sliding bean bags across a wood floor, to each other or at a target, are fun ways to gradually increase prone time. Moving like a snake or a lizard on the floor is another fun possibility. Targeted rhythmic movements and primitive reflex integration movements from the Brain and Sensory Foundations training are excellent for developing core strength and improving postural control; these activities help children gain the strength to be in prone position with more ease and comfort. When introducing movements in prone a gradual approach is best, because otherwise being on the belly can be too taxing and uncomfortable for children. However, once children receive more prone activities paired with reflex integration, they can more easily be in prone while continuing to build their core strength and postural stability—see this example, and this video example.

Why I No Longer Recommend This Technique for Encouraging Prone Positioning

For helping babies and children who are uncomfortable in prone, I used to recommend starting by putting a bolster or pillow under the chest to help elevate the upper body in order to make the prone position easier for them. While this may be helpful in small amounts, according to Porter, this practice should be avoided and only used sparingly because it “…rotates the rib cage backward, which arches and compresses the spine and disconnects the natural action of the core” (Porter, 2017, p. 71).

Encouraging Prone Time in Infancy

Here as some tips I learned from Kathleen Porter’s book, Healthy Posture for Babies and Children (Porter, 2017) that can help a reluctant baby to engage in more prone time:

• The parent lies tummy down face-to-face with the prone baby to engage the baby with play while on the floor.
• Parents place the baby in prone on a bed with the parent sitting on the floor facing the baby
• Parents can massage, sing, and speak softly to their babies while the infants are on the belly.
• If the baby is comfortable in supine, start there and see if the baby will allow slow side-to-side rolling, and eventually work up to rolling the baby all the way into prone.

In my experience, the most effective, enjoyable, and quick method for helping babies and children to be comfortable and strong prone is to give them innate rhythmic movements from the Brain and Sensory Foundations program.

Conclusion

When infants do not spend enough time in prone it can have very detrimental consequences resulting in compromised development. As a society, we can decide to rethink the idea of supervised tummy time, and embrace belly-to-earth as a baby’s most natural and optimal positioning for development. When we do this, I trust we will see many more babies who are happy and healthy with a strong foundation for well-being through their childhood and adult years.

Acknowledgement

I am deeply thankful to Kathleen Porter for her outstanding work to promote healthy posture for human beings of all ages. More than anyone else, Kathleen Porter helped me to understand the importance of “belly-to-earth” in infancy and how it is necessary for optimal development. I highly recommend her books and website resources.

References

Ballardini, E., Sisti, M., Basaglia, N., Benedetto, M., Baldan, A., Borgna-Pignatti, C., & Garani, G. (2018). Prevalence and characteristics of positional plagiocephaly in healthy full-term infants at 8–12 weeks of life. European journal of pediatrics, 177, 1547-1554.

Collett, B. R., Wallace, E. R., Kartin, D., Cunningham, M. L., & Speltz, M. L. (2019). Cognitive outcomes and positional plagiocephaly. Pediatrics, 143(2).

Kahn, A., Groswasser, J., Sottiaux, M., Rebuffat, E., Franco, P., & Dramaix, M. (1993). Prone or supine body position and sleep characteristics in infants. Pediatrics, 91(6), 1112-1115.

Ladányi, E., Persici, V., Fiveash, A., Tillmann, B., & Gordon, R. L. (2020). Is atypical rhythm a risk factor for developmental speech and language disorders? Wiley Interdisciplinary Reviews: Cognitive Science. 11(5), e1528.

Lense, M. D., Ladányi, E., Rabinowitch, T. C., Trainor, L., & Gordon, R. (2021). Rhythm and timing as vulnerabilities in neurodevelopmental disorders. Philosophical Transactions of the Royal Society B, 376(1835), 20200327.

Mawji, A., Vollman, A. R., Hatfield, J., McNeil, D. A., & Sauvé, R. (2013). The incidence of positional plagiocephaly: a cohort study. Pediatrics, 132(2), 298-304.

Paluszynska, D. A., Harris, K. A., & Thach, B. T. (2004). Influence of sleep position experience on ability of prone-sleeping infants to escape from asphyxiating microenvironments by changing head position. Pediatrics, 114(6), 1634-1639.

Porter, K. (2017). Healthy posture for babies and children: Tools for helping children to sit, stand, and walk naturally. Healing Arts Press.

Togari, H., Kato, I., Saito, N., & Yamaguchi, N. (2000). The healthy human infant tends to sleep in the prone rather than the supine position. Early human development, 59(3), 151-158.

Zablotsky, B., Black, L. I., Maenner, M. J., Schieve, L. A., Danielson, M. L., Bitsko, R. H., Blumberg, S. J., Kogan, M. D., & Boyle, C. A. (2019). Prevalence and trends of developmental disabilities among children in the United States: 2009-2017. Pediatrics, 144(4).

Zoccante, L., Ciceri, M.L., Chamitava, L., Di Gennaro, G., Cazzoletti, L., Zanolin, M.E., Darra, F. and Colizzi, M., (2021). Postural control in childhood: investigating the neurodevelopmental gradient hypothesis. International Journal of Environmental Research and Public Health, 18(4), 1693.