If you have just taken up swimming, you’re most likely working on building your endurance and improving your craw stroke. You’re probably totaling a distance of 500-600 yards, breaking it up every 100 yards swimming slowly and relaxed.
You will not get much better unless you work on your core. Take a day to focus on drills that strengthen the entire core – abdominals, lower back, bum, upper back and shoulders. Crunches are a good start but they limit the muscles range of motion. You need a strong overall base of support from which your limbs can generate the force to propel you though the water.
Your arms and legs can be relaxed at certain points of your swim but your core never rests – from the glutes to neck. A strong core means you’re going to be swimming in a straight line, which saves you energy so you can keep swimming.
Stretch through your core. Do the Cobra. The muscles that stretch your spine forward are at work, especially in the belly. Lie down with your hands on the floor right under your shoulders. Lift your head and torso until you feel the stretch. Hold for 20-30 seconds.
Do Y-T-W-L exercises. They work every back muscle you have like nothing else.
Squeeze your glute muscles. This exercise helps for a better kicking technique. Some very helpful exercises out of the pool are single-leg bridge, climbing stairs, leg extensions and squats.
Don’t forget your posture. It’s crucial for your swimming technique. You may be slouching and not even realizing. And before you know it your neck and spine are bent you swimming gets more and more difficult. Keep your shoulders back and chest straight while swimming (just as you should while doing anything else).Hunched shoulders leads to swinging your arms wide instead of over the top of the body. Bad posture also leads to cross-overs.