Here's a funny fact: healthy bodies move in perfect form all through our early childhood. We engage through our core, when pushing a heavy object, squatting to pick up a toy, or sitting at dinner table. Then, at some point between then and adulthood our mother started saying, "don't slouch, dear."
When did that happen, and why?
I'm not going to get into all the theories about core strength loss and what it's effect on our low back/race times/basic movements (mostly because I have a preschooler nearby who wants to PLAY. Now!), but I will share this: most of us (exercisers included) have room to improve, and benefits to gain. Good ones, too.
Here are two simple tests you can do -- for fun (because you're not a pro) -- to determine what you need to work on regarding your core.
TEST 1: Whether you're sitting or standing right now, lift one foot off the ground (knee lift & hold). Did you feel the muscles that cross your abdomen tighten just before doing so? If not, it's a sign that your neuromuscular system has found a new, alternate way to do things, and your core hasn't been invited. This is not good. Using smaller muscles to do the work of your mid-body muscles can lead to dysfunction and injury.
Failed the knee lift test? If you're pretty sure you didn't engage your core when your knee went up, then it's dead bug time for you! Practicing this exercise for 10-20 reps at least once per day will help reacquaint your body with your core. Once those neuromuscular pathways have been reunited, they will become automatic.
TEST 2: Try to hold an elbows and toes plank for as long as you can, up to 90 seconds. If you can't make it without rest or sticking your tush above the imaginary line that connects your ankles and shoulders, it may be a sign that you need to spend more time on core work.
To examine whether you're executing your plank correctly, you can watch this video. Also, find an objective eye (your video recording app or another person) to assess. If you notice any of the three issues I describe in the video, then it also can signify a weak or under-accessed core. There are some good tips in my first follow-up video workout, meant for those who tend to drop their hips in plank.
Did you fail the plank test?
Here's your plan for improvement: Three-to-four times per week, spend 5 extra minutes focusing on your core. The workout should involve ALL core muscles, not just your abdominal muscles.
Here's one example of a well-rounded 5-minute workout: Dead Bugs, Single-Leg Dead Lifts, Superwomans, Plank, Side Plank. One minute each.
Here's a BANK of 5-minute core workouts that I created last winter that you can follow along with!
More motivation needed?
Here are some of the BENEFITS of Strengthening your Core
Reduced injury risk (less 'starting over')
Faster running/cycling times/pace (happy racing!)
More extremity strength (best 4-minute push-up score ever?)
Healthier back (pain-free)
Better Balance (Reduced risk of falls)
Easier time completing daily tasks (more energy for the fun stuff)
Better posture! (your mother will easily find something new to nag you about)
All of these thing benefits can lead to a better-functioning, better-looking, and happier you!