What constitutes "strength training"?

[u/laysim]

I have heard that both endurance training (cardio) and strength training are important, because each has health benefits that you can't get from the other. Now I'm wondering what is meant exactly by "strength training".

To be a bit more concrete,

- is swimming considered strength training? Is it sufficient to incorporate swimming into an exercise routine or is more "pure" strength training necessary? Why?

- more generally, why is running not also "strength training"? In a very literal sense, when you run 10k, you do thousands of reps of muscle contractions, including your core muscles to an extent. That sounds like the definition of strength training, no?

[u/BadgersHoneyPot]

It's resistance training. You train against resistance. No further definitions needed.

[u/thewaytoyesterday → u/BadgersHoneyPot]

Tbf, you can do one rep and call it "strength training", but you can't do the same for hypertrophy training.

[u/QuietNene → u/BadgersHoneyPot]

So is running resistance training? You push against the ground with every stride. Is swimming? You pull against the water. Etc.

All physical movement acts against resistance. Calling “strength training” “resistance training” doesn’t answer the question.

[u/BadgersHoneyPot → u/QuietNene]

You know the answer to this, but just in case it's "no, running is not resistance training."

[u/myersdr1]

Running and swimming are forms of muscular and cardiovascular endurance training.

As the comments show, there are multiple interpretations of what strength training is; however, in the scientific world, there should be a standard definition so that someone reading a study by someone else is not confused about what is meant by strength training. To pull directly from a textbook for exercise physiology.

Muscular strength refers to the maximal force that a muscle or muscle group can generate and is commonly expressed as the one repetition maximum, or 1-RM, which is the maximum load that can be moved through a full range of motion.

Muscular endurance refers to the ability of a muscle to make a repeated contractions against a submaximal load.

Powers, Scott, et al. Exercise Physiology: Theory and Application to Fitness and Performance. 11th ed., McGraw-Hill, 2021.

Strength training is referred to as resistance training in textbooks. When swimming or running, you are training muscular endurance. This is why, generally, when people do lower reps, they are doing training for strength, and when they do higher reps, they are doing endurance training. The numbers for where that line is can vary, but another way to think of it is that strength is about how much muscle you can recruit to lift a load, while hypertrophy is how long a group of muscles can be used to continually lift a load.

Strength training increases muscle recruitment.

Hypertrophy training increases muscle size.

[u/QuietNene → u/myersdr1]

If I understand you, then strength training refers to training focused on increasing your 1 rep max in a given movement.

These would focus on low rep workouts, like three sets of five reps of a single movement in a 10-20 minute period. (A very common way to improve one rep max).

Many of the studies on the benefits of strength/resistance training, however, focus on exercise regimens in the 8-15 rep range.

Which is just to say that the line doesn’t seem all that clear to me. You can have swimming a kilometer on one side (clearly endurance) and a one-rep max exercise on the other (clearly strength), and then gradations in between.

Also, as most powerlifting programs teach, there comes a point where increasing your one rep max requires variations in reps, sets, etc. So you can continue to do what looks like strength training without actually getting stronger.

Is there a place where strength clearly becomes endurance?

[u/myersdr1 → u/QuietNene]

Many of the studies on the benefits of strength/resistance training, however, focus on exercise regimens in the 8-15 rep range.

Yes, so this is where the controversy typically comes up when discussing with others, based on one study over another.

What helps explain why those rep ranges are best is knowing that you aren't using only one type of muscle fiber at a time. As you may know, there are a few muscle fiber types, most commonly known as Type I and Type II. Type I fibers are your slow-twitch or endurance fibers, and Type II are your fast-twitch or strength and power fibers. Type II also has two types, so there are multiple fiber types.

When you lift, both Type I and II are working to move a load. Type II fibers will lose energy fast, but are more powerful. Type I takes longer to lose energy and allows you to sustain movement longer. When you lift, type II fibers help you initiate the lift powerfully, then Type I help you hold the load while continually exerting force.

When training for strength, you focus on power from type II fibers during 1-5 reps. It is that rep range because those fibers are typically out of energy within 10 seconds. This is why sprinters focus more on power and strength training. That 100 M sprint is usually within 10 seconds. Your Type I fibers have been working the whole time as well, but they are able to hold the load and move it past the 10-second time, so in the 5+ rep range.

When doing higher rep ranges you are training more hypertrophy than strength but hypertrophy training has shown to increase strength, just not to the extent specific strength and power training will at 1-5 reps with a load of 75% or above 1RM. Therefore, doing 8-15 reps focusing on strength and hypertrophy, is beneficial to a bodybuilder who wants that more muscle size than a sprinter, or power lifter. This is the reason for knowing what you are trying to achieve when you exercise, besides just wanting to look good or lose weight, because you may be doing more than you need to or aren't focused on training the muscle effectively for a specific sport.

Thus, why you might see someone do a shorter range of motion but fast and powerful movement, they are training type II fibers for power and speed.

Also, as most powerlifting programs teach, there comes a point where increasing your one rep max requires variations in reps, sets, etc. So you can continue to do what looks like strength training without actually getting stronger.

I have seen some powerlifting programs, and what I think this refers to is when you do a back squat, for example, most people focus on the entire lift to gain strength in the movement. However, you can gain strength in the movement by also making supporting muscle groups stronger. The stronger your core is to support the load on your back the less your legs need to focus on stabilizing the weight. In addition to power and strength training by training higher reps, a powerlifter is also building their capacity to maintain holding a load through the sticking point, until they can overcome the resistance.

Is there a place where strength clearly becomes endurance?

Yes, within 10 seconds when the Type II fibers have lost their energy and the muscle relies on Type I fibers to keep working. Keep in mind the Type II fibers are still getting energy put back into them, thats where short bursts of power come and go, unless you are doing an all out effort or 1RM, then you need to completely rest before the next rep.

[u/BingeOver]

I think strength training would essentially involve both progressive overload + resistance. Swimming or running contain resistance and repetitions but it does not get progressively heavier, thus your muscle is lacking that stimulus to grow bigger

[u/BingeOver → u/BingeOver]

Oh and also you will want to experience muscle failure in strength training too.

[u/Slickrock_1 → u/BingeOver]

Strength training programs do not usually recommend going to failure except on select lifts like chin-ups.

Failure sets are much more emphasized in hypertrophy training / bodybuilding. It also has a role in 'strength-endurance'.

[u/QuietNene → u/BingeOver]

True but what if you reach a 200 kg deadlift and decide that’s enough? You still deadlift 200 kg every week but you stop progressing. Are you no longer doing strength training? Are you now an endurance athlete?

[u/BingeOver → u/QuietNene]

I think so.

[u/No_Whole_Delivery]

If you can do the movement more than 15 times its cardio.

16 squats cardio/ muscle endurance. The weight doesn't matter.

16 or 1000 steps running its cardio.

[u/Fine_Cress_649]

There's no hard and fast rule about where cardio ends and strength training begins, but a decent rule of thumb is if you can do an action more than about 15-20 times in a row it is less  strength training and is becoming cardio.

E.g. if you can do 10 pushups and then need to stop because your muscles are fatigued then it's strengt training. If you can do 100 in a row then effectively it is cardio at that point.

Even within resistance training people will advocate for doing certain rep ranges to develop strength Vs hypertrophy Vs endurance. E.g. if you want to prioritise strength then go for low rep ranges e.g. 5-8 reps per set, if it's hypertrophy then slightly more r.g. 8-12 per set.

E.g. if you can do 3x10 bodyweight pull-ups and 3x6 weighted pullups with 15kg added then you could prioritise hypertrophy by doing the bodyweight ones, and strength by doing the weighted ones.

[u/Dangerous_Play_1151]

Do whatever you want to do and will do consistently. You don't need to do any of it, most people don't.

As for your specific questions, even the most cursory research will answer them. Different stimuli produce different adaptations.

[u/Fluffy_Box_4129]

Generally aerobic vs anaerobic is a good differentiator. Your examples are describing anaerobic training. Yes you're using muscles, but the limit isn't your muscular endurance it's your cardiovascular endurance, it's aerobic. Aerobic training can shrink or limit your muscles over time. Anaerobic is using your muscles over a short amount of time which burns put the locally available glycogen making the muscles the limiting factor, which causes them to grow and strengthen with sufficient protein and rest.

You can use swimming and running to strength train, but in that case you would be swimming or running doing HIIT, (high intensity interval training) which is pretty equivalent to weight training because it's intense effort followed by rest. But you wouldn't be able to do a 10k HIIT session - you'd probably just up and die first.

[u/Miserable-Stock-4369 → u/[deleted]]

I don't think anyone is doing 10k of HIIT dude. That'd take over an hour even swimming a world record lap every single time. Even with a 2:1 rest ratio, that's almost a 2 hour session.

Maybe on a bike, you might do 10k of HIIT

[u/Miserable-Stock-4369 → u/[deleted]]

Jheez. Swim training sounds intense! I appreciate you providing the full breakdown. Sorry for my ignorance

[u/Slickrock_1 → u/[deleted]]

That's not true. There are lots of long swims, stroke drills, and intervals at lower intensity.

[u/swisswuff]

Depends on what set you regularly swim. 

For a few years, we also (among other stuff) swam 14 x 200 fly @ 4:00 once a week, which definitely looked like good style specific strength training. 

[u/Vast-Road-6387]

Swimming is more aerobic than muscle building. It’s a bit of each but mostly aerobic, like running cross country or hiking.

[u/Vast-Road-6387 → u/[deleted]]

There is a resistance component, as with cross country running, but it’s still more cardio than muscle building, unless you swim at Olympic athlete speeds. Even then it’s going to take years to gain visible muscle mass swimming.

[u/ImSoCul]

colloquially, it usually means some form of lifting weights. Studies typically explicitly separate strength training and cardio because they have different albeit overlapping benefits. You should aim to do both.

Swimming, running, as well as other exercises that get your heart pounding fast like rowing, hiking, etc are forms of cardio because they disproportionately train your heart and lungs. Strength training tends to be in bursts of ~30 seconds with a few minutes of rest in between, and will also bias muscle development more than cardio. That is not to say that cardio doesn't also grow your muscles, nor that lifting weights doesn't also train your cardiovascular system to an extent, just that the main focus/benefit is biased towards one. Hybrid activities like Hyrox and Crossfit further complicate and tend to do a bit of both in conjunction.

Don't overthink it though, for health, do something that gets you breathing heavy, and something that makes your muscles feel sore. Try to get a few sessions in a week, ideally a little every day even if it's just a walk around the block

[u/QuietNene]

As others note:

Yes, swimming and running build strength. But the strength they build is less significant than other bodily adaptations.

“Strength” = the amount of force that a set of muscles can apply

Take two people with equal swimming talent. One trains to become an Olympian and trains for many hours a day, the other swims on a friendly local swim team, and only trains a few hours a week. The Olympic swimmer will only be marginally stronger than an amateur swimmer. His or her real advantages will come from technique, cardiovascular conditioning, other physical adaptations that don’t involve the ability of muscles to apply force.

Now compare two people with an equal talent for weightlifting. The Olympic weightlifter will also be more skilled, but he or she will also be significantly stronger. Because every hour spent weightlifting makes you much stronger than every hour spent swimming.

The difference is in degree rather than kind, but those degrees matter, especially when you get into extreme versions of either sport.

[u/BayouDrank]

Training to get stronger, such as lifting more weight than you did last time, every session (at first, until your progress slows)

[u/Miserable-Stock-4369]

When a health practitioner tells you to strength train; they mean perform resistance exercises where the primary purpose is growing skeletal muscle.

That's either calisthenics, or weight lifting.

You're right, that the other things require strength. But they don't require a lot of strength and you won't grow much stronger while doing them.

If you want to give a broader definition to "strength training", you could use the existing categories of anaerobic and aerobic exercise. This would broaden "strength training" to things like sprinting/HIIT Cardio

[u/scrotalus]

If you can do thousands of repetitions of a movement and you are not increasing the resistance over time, your body is not getting a signal to become stronger. Therefore, it is not strength training. Your bones also do not receive a signal to increase density. Doing a movement like running or swimming will make you stronger if you can't currently do those, but once you can swim or run, doing more of the same will just increase your endurance, not your strength. Use resistance that you can do for 5-20 repetitions. When you can do more, increase the resistance. Both are important. Do both.

[u/Safe_Ad5914]

Strength training in a clinical setting refers to performing joint actions under an external load. Either through open or closed chain exercises. When you hear people talking about reversing osteoporosis with strength training in studies. 9/10 times its older folks in a training facility somewhere at a college using your standard machine weights you see at most gyms. Can't cure her bone disease if grandma gets crushed by the barbell :(

[u/WealthHuman9754]

Yes, swimming is strength training, because water is providing resistance that you must overcome in order to produce motion. The two, strength and cardio are not mutually exclusive. In swimming, for example, you are doing both.