A reflex is a muscle reaction that happens automatically in response to stimulation. Certain sensations or movements produce specific muscle responses. Newborns are born with specific reflexes that are intrinsic and either disappear in the first few months of life or are carried on throughout adulthood. Having a basic understanding of which reflexes are present can help instructors to observe and understand the physical reactions some infants may display while in a swim lesson. It is important to note that the degree of the observable reflex response can vary from infant to infant and may recede at variable time frames. This being the case, it is recommended that instructors DO NOT SOLELY RELY on certain reflexes to help, protect, or aid the infant during the introduction of various skills. However, they can be a useful tool to incorporate, direct, or capitalize on certain movements.
Brief descriptions of applicable reflexes to the infant/toddler swim lesson:
Moro Reflex (Startle Reflex)
The symmetric abduction and extension of the arms, noted when a loud noise is heard or when, holding the infant in a semi-sitting position, the head and trunk are allowed to fall slightly backward with support. Arms are adducted in embracing motion and then return to relaxed flexion and movement. This is an intrinsic protective reflex and disappears between 2-3 months of age. The Moro reflex may be seen as infants are brought into the water or if they are “startled” by a loud noise. Environments may need to be adjusted in order to create a more calming environment for the infant and parents may need to be reassured of the baby’s initial, natural response to being placed in the water.
When placed in a supine position and pressure is applied to soles of feet, both lower limbs should extend against the pressure. This reflex may be observed or utilized in the swim lesson by placing the infant in the back floating position and putting both of the infants feet against the wall. The infant will push off of the wall.
Palmar and Plantar Grasp Reflex
When an object (finger/toy) is placed in the palm of the infant’s hand or at the base of the toes, the infant’s fingers will curl around the object and the toes will curl downward. This can be applied to the swim lesson in various ways. It may be utilized to give the child some balance by providing a supportive finger, or some comfort by providing a toy to play with.
When infant is placed on abdomen, the infant will make crawling movement with arms and legs. When in the water, this crawling reflex may be misinterpreted by parents as actual swimming when it is merely a reaction to the position. Parents may see these motions and think that their child is learning to swim! This is not a reflex that can be learned or taught. It will disappear as the child gets older (around 4 to 6 months). Instructors may be able to capitalize on these natural movements by encouraging parent to gently move them through the water during these movements .
Tonic Neck (Fencing) Reflex
When infant is in a supine, neutral position with the head turned to one side, the arm and leg on that side will straighten, while the opposite arm and leg will bend up. This gives the infant the appearance of being in the “fencing” position. This reflex may be very obvious or very subtle, with the leg response being more consistent. This reflex may be observed, again, when the child is on their back in the water. Instructors should be aware that this position may be a natural response, not necessarily a dislike or refute of the position, and does not always require immediate correction.
Diving Reflex or Bradycardia Response
The diving response involves reflex bradycardia (slow heart rate or heart rate less than 60 beats per minute), apnea and peripheral vasoconstriction and is known to exist in mammals, including human infants, when submerged in water. It has been taught that infants up to six months old will naturally hold their breath when submerged under water, while at the same time, slow their heart rates in order to help them conserve oxygen and redirect blood to the vital organs, the brain and heart. While this response has been clearly shown to exist, for the purposes of this class, it is recommended that this response NOT be counted on to occur for swimming instruction of the infant. The reason for this is that various factors (age, water temperature, depth of submersion, length of submersion, angle of submersion,etc) need to be considered in order for this response to be reliably initiated.
Special Note: Some infants under 6 months of age have displayed an apneatic response after submersions over three seconds. (suspension of external breathing; during apnea there is no movement of the muscles of respiration). The infant’s breathing usually starts spontaneously after surfacing, but this can be delayed and cause understandable distress when observed. While the understanding of this response is still cause for some debate, the Association’s position has been to advise limiting submersion times as described above until the infant responds to cues, cognitively initiates breath holding, and/or is older than 6 months, at which time the length of submersions may be extended, if the child is comfortable.
If water accidentally does get into an infant’s mouth, it is unlikely to be inhaled. Instead the gag reflex kicks in closing off the entry to the airway, at the entrance to the larynx. An involuntary spasm causes the epiglottis to close over the larynx, creating a watertight seal and preventing inhalation of water into the lungs via the trachea. Usually an involuntary cough occurs soon after to blow the water out of the back of the throat. The reflex is well defined at birth and diminishes over the first 12-18 months of life. The reflex is partially in place into adulthood.
- Working with the babies, we should NOT rely completely on this reflex. It is important to slowly and carefully prepare the child for submersions with lifts, counts, letting them feel the sensation of water over their heads, etc. These verbal and non-verbal cues are excellent for preparing the babies for submersions without fear and tears.
- The gag reflex does have its limits. While it does close off the windpipe, it does not close off the esophagus leading to the stomach.
- This is why it is important to limit submersions to less than 6 per class session until breath holding is demonstrated. A child may be a “quiet drinker”. They do not always gag if they swallow water.
- To trigger the reflex effectively submerge the entire head and allow the baby to build up to submersions lasting up to 3 seconds.