Blog - Swim Jim


Ever wondered why your skin wrinkles up like a prune in the water?

Anyone who has taken a long bath or gone for a swim can attest to a certain pale pruniness of the skin that goes away harmlessly after a little while. And anyone who has spent a day at the beach splashing around can vouch for the fact that you get unduly fatigued from it all.

The answers are pretty interesting: did you know that your skin is water proof! I myself had never thought about it until now but truth be told none of us soak up water like a sponge. The reason is that the sebaceous glands in your skin produce an oil called sebum (SEE-bum) that acts effectively as water-proofing while also lubricating and protecting your skin. We tend to think of ourselves as walled off under our skin but it is actually this sebum that keeps us from bloating up with water every time we get into the pool.

When you go swimming, you lose this protective layer and your skin suddenly becomes more porous. Perhaps you remember the concept of osmosis from high school biology. Well, essentially, without that protective layer, the lower density of water in your skin relative to the pool, pulls water molecules into the top layer of your skin and stores it in your fat cells, via osmosis.  This process tries to  balance the water pressure difference between you and the pool and stopping at saturation point (i.e. wrinkly pruny skin.)  This layer is attached to the layer below that does not absorb water and the combination of being fixed down and the increase in size of the top layer leads to wrinkly skin.

An interesting aside is that swimming in the ocean, whether just a quick jaunt or a dive for pearls, will never leave you pruny and water-logged. Why? Well, it goes back to osmosis. When you are in a pool, the salt concentrations of H2O in your skin are higher and so the water from outside goes in. Well, when in the ocean, the salt content in the sea water is much higher and therefore draws the water in your skin, after the sebum has rubbed off, out into the ocean.  Can you imagine?  Your body trying to equalize the salt content of the ocean?  That’s a lot of water to give off.  So…

This highlights the important fact that should be remembered in the Summer when you are making a trip to the beach. If osmosis is working against you in salt water (taking water from your skin cells), then you need to counteract this by drinking extra water or a drink like Gatorade that is full of electrolytes. Doctors suggest about 8 cups of water a day, more if you are going to be active. We suggest 15 cups of water to drink a day, which is roughly equivalent to about 10 cans of soda. This might seem a lot but just remember that with the combination of that sun beating down on you, and the salt water sapping H2O from you, it’s crucial that you stay hydrated while having fun in the surf and sun!


Pre-natal Swimming, part one

Get exercise and go weightless! As swim instructor and five months pregnant with my first child I have found that being in the water has incredible benefits for not only me but my baby as well. The added weight and tension on my body is completely lifted in the water, even when I’m teaching a group of four children! Swimming is a low -impact way to get cardio and improve muscle tone, not to mention how great you will sleep in between night time bathroom runs. Swimming is an ideal form of exercise through your entire pregnancy. Whether you are getting to know moms-to-be at a pre-natal swim class or enjoying the solitude of you own swim lane, water exercise is a fantastic way to benefit you and your baby before and after your due date. As with any new exercise regimen it is always best to speak with your doctor or midwife before beginning. Please check back for more information about pre-natal swimming, exercises, and class information!



Swine flu, like the avian flu in 2006, has gained a lot of press as it quickly spread throughout the developing and emerging world.

The imagery of large crowds wearing surgical masks and wholesale slaughter of entire livestock populations adds further intensity to an already serious situation.

At SwimJim, we are not doctors but, as child educators, it is incumbent upon us to educate ourselves with information from national and local authorities. We want to be prepared and help you prepare yourself and your family.
Following the National & Local Authorities

The Centers for Disease Control & Prevention’s site has the lastest statistics and information for swine flu around the entire country. It also has recommendations for public health professionals at the local level. You can sign up for real-time email or RSS feeds from the CDC on their site or follow them on Twitter (“CDCemergency”).

Because decisions like school closings are made by local government agencies, we also went to county health websites for our various locations, such as Houston’s Harris County Public Health website. They have a special swine virus resources page that contains several useful PDFs including how to protect yourself and your family and key facts about swine flu in humans. The majority of these documents are available in both Spanish and English.

What Did We Learn?

We learned some interesting things about swine flu, how it is spread and how to protect ourselves.

1) Every single resource we read mentioned vigorous and vigilant hand-washing as a primary means to minimize infection.

2) See your physician immediately if you or your child feels ill or demonstrates the following symptoms: fever over 100′; exhaustion; lack of appetite; coughing, sneezing and other flu-like symptoms.

3) You can’t get swine flu from eating pork.

4) If you are sick, stay home.

5) Swine flu is very treatable in humans but widespread immunization is not being pursued. At the moment, the authorities are focusing on immunizing hospitalized patients and other minorities with increased predisposition to getting flu and flu-like diseases.

6) Swine flu is not believed to be more dangerous than the common flu we are all familiar with.

Thank You
We hope you find this helpful.

Please give us your feedback and comments. We’d love to hear from you!


The SwimJim team