What Muscles Do I Use When I Swim?

When it comes to an overall workout, there is nothing that compares to swimming.  Cardio, strength, and range of motion are all vital parts of swimming.  No one has ever done a full swim workout and got out of the pool feeling great.  It tears you down, wipes you out, and downright brings you to your deathbed.  But we keep coming back for more because the long term effects are incredible.  Increased lung capacity, endurance, flexibility, willpower, and strength. So exactly what muscles are you using during a swim workout? Well let's take a look!

Cardio Muscles:
                              

Two muscles that are VERY important to your body's general function (not to mention keeping you alive...I guess that's kind of important too) are the heart and lungs.  Yes these are muscles!  They are what are called "involuntary muscles" because you cannot control whether they are working or not.  Your heart pumps blood to all different parts of your body, including your lungs.  Your lungs take in all of that air your breathe and put oxygen in your blood.  This oxygen-rich blood helps your muscles perform to their maximum capabilities.  Ever had that sprint for the finish? You just put your head down, hold your breath, and swim like crazy for the wall.  The reason that holding your breath while trying to exert maximum effort hurts so bad is that your muscles are getting deprived of that oxygenated blood that they need to thrive. But you do it anyway right? Because holding your breath=faster swimming!

Freestyle Muscles:

All of the muscles that are circled in the picture above are muscles used when you swim freestyle.  There are 24 different muscles circled in this diagram. The ones that are circle in blue are more primary muscles that are worked and the muscles circled in black are the more secondary muscles exercised. Here they are in a list form: 

Arm: Thenars (hand muscle), brachioradialis (forearm flex muscle), flexor digitorum profundus (forearm extend muscle), biceps (sometimes referred to as GUNS), triceps, deltoids (shoulder muscle)

Neck: sternocleidomastoid (neck muscle)

Trunk: pectoralis, serratus anterior (side muscles), external oblique (outer ab muscles), rectus abdominus (abs), latissimus dorsi (back muscle), trapezius, spinus erectus (muscles that support your spine), teres major, teres minor, rhomboid major, rhomboid minor (all of these "major and minor" muscles help make up the shoulder muscles), gluteus maximus (rear-end muscles), abductor magnus (groin)

Leg: quadriceps, hamstrings, gastrocnemius (calf muscle), tibialis anterior (shin muscle), flexor digitorum brevis (foot muscles)

Funny how a lot of these sound like spells straight out of a Harry Potter book, huh?

Can you imagine trying to flex all of these muscles at one time?  Or trying to use weights to try and work out these muscles?  In the pool you use each of these 24 different muscles on each freestyle stroke! And if you think about it, since these muscles are on each side of your body, you have to double the amount and you are really using 48 MUSCLES!!! Some of the muscles are used when pulling, some when kicking, some when rotating your body, some when breathing, and some extra muscles you use when doing flipturns. Below is a really amazing video created by AnyBody that shows and highlights when the different muscles are used when you swim freestyle. This is unbelievable:

Backstroke Muscles:

The backstroke muscles are identical to the freestyle muscles except they are worked during different times of the stroke.  If you think about it, backstroke is kind of like freestyle on your back.  One thing about these two strokes that is helpful to remember is that - generally - backstroke stretches out your freestyle muscles and freestyle stretches out your backstroke muscles.  That is because they are both utilizing the same muscle groups, but in a different movement.

I would suggest trying out this easy way to stretch out during a cool down. You can really tell the difference! Below is another great video of what muscles are used when during backstroke:

Breaststroke Muscles:

The muscles used are about the same for breaststroke and butterfly as freestyle.  It is just a slightly different group of primary muscles used.  The primary muscles used in breaststroke are the hand, inner forearm, biceps, pecs, lats, groin, glutes, and calf.  One difference in muscle use during breaststroke is that there is a slight relaxation point of almost all muscles when the swimmer is gliding.  The only muscles used during the glide are the ones to old a streamline position.  This is one reason why sometimes breaststroke can be known as an easier stroke sometimes.  Below is another one of these awesome videos showing when different muscles are used during breaststroke:

Butterfly Muscles:

Once again, the butterfly muscles are roughly the same as the other strokes.  There are a lot of big muscle groups used in butterfly.  That is why it is commonly considered a very powerful stroke and can wear you down in a matter of 25 yards.  Pecs, lasts, quads, hamstrings, calves, shoulders, biceps, and triceps are all big-time power muscles.  Here is one more video of what muscles are used when during butterfly: 

Now you know what muscles are used, when they are used, and how some of them are used.  It should give you a better idea what exactly you are doing when you are swimming. Now you know why swimming is a harder and more all around workout than almost anything else you can think of!

And as a bonus, here is the video of all four strokes put together: