Very often our mothers refuse to question the rationality of those rules they set as they turn a blind eye to the scientifically-proven truth. So once again, they force us into complying the rule of no swimming after eating without seeking for the correct explanation.
The truth behind this myth has been debunked by both sources of scholarly literature on athletic swimmers and of website articles on recreational swimmers. In particular, Franco (2015) found that swimmers often ate a meal before their swim to attain the energy they required. From striking in the water, the body produces adrenaline that enhances oxygen supply to the muscles, which require oxygen the most. Hence, even if cramps were to happen, it will not be as severe to result in drowning (Franco, 2015).
Although it is true that the body does supply extra blood to the stomach for digestion, as shown by the increase in cardiac output towards the gastrointestinal tract (Dukemedicine.org, 2015; Iversen, Dupont-Prinet, Findorf, McKenzie & Wang, 2010), there is still adequate blood supply for the upper and lower limbs, and blood is not redirected from other vasculature (Iversen et. al., 2010).
The Center for Disease Control and Prevention and the World Health Organisation both state that eating before swimming is not a risk factor for drowning (Cdc.gov, 2015; Who.int, 2014).
Expert swimmers will normally eat right before swimming to have sufficient energy for higher performance level competition especially in long distance such as triathlon. (Read, 2014).
If cramps do happen to occur while swimming after a meal, it is advisable that the swimmer should not panic (Julia, 2011). The period of cramps does not prolong and naturally the body tends to float (Julia, 2011).
There is very little information on the effects of eating a meal before swimming and not waiting 30 minutes. Overall, evidence based literature supports that there is no harmful effect on eating a meal and not waiting 30 minutes to go for a swim.