Forearm Training: How to Build Bigger Forearms
When you first start lifting weights, it’s a good idea to focus most of your energy on the big compound lifts. Your workouts start with lifts like the squat, bench press, deadlift, chin-up, and row. These are the biggest lifts that build the most overall muscle mass. After that, we add in some isolation lifts. Curls for our biceps, extensions for our triceps, lateral raises for our shoulders, and maybe some exercises for our abs. These train the muscles that aren’t properly stimulated by the big compound lifts.
As you gain weight, build muscle, and get stronger at these lifts, you’ll probably notice that your grip is getting stronger, and your forearms are getting bigger. This is because the rows are training your elbow flexors, the biceps curls are training your wrist flexors, and the lateral raises are training your wrist extensors. They aren’t the main muscles being worked, but since we’re new to lifting weights, they grow.
The thing is, as you continue getting bigger and stronger, you’ll probably notice that your forearms stop growing. That’s because your forearm muscles have gotten both stronger and tougher, and these compound lifts aren’t challenging them enough to provoke any growth.
So how do we get bigger forearms? We train them directly. Here’s how.
Average Forearm Size
When looking for average body-part measurements, we normally look at measurements taken by the CDC. But forearms aren’t a common body-part to measure, and we don’t have that data here. Fortunately, if we look at the research of Dr Casey Butts, he estimates that the average 165-pound untrained male has a forearm circumference of about 12 inches.
- Skinny forearms: 11″ circumference or less (been there!)
- Average forearms: within an inch of 12″ circumference
- Big forearms: 13″ circumference or more
Now, what should we do with that information? I saw a post on Reddit from a skinny who wanted to know the average forearm size. He was tired of having skinny forearms, and he wanted to build his forearms to that size. Pretty reasonable, I thought. But the top commenter had a different idea:
Your forearms are X inches.
Scenario 1: you set a goal of Y inches: you train optimally, eat optimally, recover optimally, and grow optimally. 6 months later your forearm diameter is X+N inches.
Scenario 2: you set a goal of Z inches: you train optimally, eat optimally, recover optimally, and grow optimally. 6 months later your forearm diameter is X+N inches.
If you want to succeed, set goals that are under your control. You cannot control the result of your training–only the process of training. For example, set a goal of lifting 4 times a week for 30 days. That’s Specific, Measurable, Achievable, Relevant, and Time-bound (S.M.A.R.T.).
SordidBear, Reddit
That’s great advice, and so eloquently worded, too. Regardless of our starting point and genetic potential, the best way forward is to work out our forearms, eat for muscle growth, and recover. Rinse and repeat for 4 weeks, measure our progress, adjust our workouts as needed, and continue onwards.
But that answer is also deeply unsatisfying, at least to me. I don’t just want to build bigger forearms; I want to know how big I should build them. Plus, I want to know what’s realistic. And fortunately, building bigger-than-average forearms is something totally realistic, no matter how skinny your forearms are right now. But what’s the ideal forearm size?
How Big Should Your Forearms Be?
Okay, so building bigger forearms is realistic, and our genetics shouldn’t be a limitation—any skinny guy can build above-average forearms. But what about the ideal forearm size? How big should we be trying to build our forearms? And is that goal realistic for the typical skinny guy?
- Ideal male waist size: you at 8–15% body fat
- Ideal male bicep size: waist × 0.5
- Ideal male forearm size: biceps × 0.8
Going back to Dr Casey Butts’ research, he estimates that your ideal waist size is your waist circumference when you’re at a pleasantly lean body-fat percentage (8–15% body fat). That’s a body-fat percentage ranging from chiselled abs to a flat stomach. From there, he says that your ideal biceps size is half the circumference of your waist. And then your ideal forearm size is about 80% the size of your biceps.
For example, at 11% body fat, my waist is 32 inches, giving me an ideal biceps size of 16 inches, and thus giving me an ideal forearm size of around 13 inches—nothing crazy, but a little bigger than average.
This gets a little more complicated if you’re still quite skinny, though. As you gain muscle, you’ll build bigger abs, obliques, and spinal erectors, so your waist size will increase. Back when I weighed 130 pounds, I had a waist circumference of 28 inches. Now that I’ve gained 65 pounds, my waist size went up to 32 inches, even though my body-fat percentage is still the same as when I started. So as you gain weight overall, expect your ideal measurements to increase a little bit.
Still, this gives us a rough idea of how big your forearms ought to be in proportion to your waist and biceps. That can give you an idea of whether your forearms are falling behind your biceps or not, in which case they might deserve some extra attention. When you do start training them directly, they’ll grow quite well. And the ideal forearm size isn’t unrealistic. It should be well within your grasp.
The 3 Best Forearm Exercises
One of the mistakes people make is thinking that developing a stronger grip will build bigger forearms. Your grip muscles are indeed located in your forearms. But those muscles are tiny, so making them stronger won’t do much to increase your forearm circumference.
To build bigger forearms, there are three different muscle groups we’re interested in:
- Wrist extensors: these are the muscles that run along the entire backside of your forearms. They aren’t huge muscles, and they can only grow so strong, but unless you work a manual labour job, they’re probably underdeveloped. By bulking them up, you can make the entire length of your forearms, from your elbows to your wrists, look more muscular.
- Wrist flexors: these muscles are the biceps of your forearms. They’re strong muscles with full bellies and great growth potential. Bulking these up is one of the easiest and most effective ways to increase your forearm circumference.
- Elbow flexors: these are the muscles we train with barbell rows, pull-ups, and reverse curls. You can bulk these up simply by getting stronger at the big compound lifts, but they’ll grow even faster if you train them directly.
That gives us 3 forearm exercises that we can use to bulk up all of the biggest muscles in our forearms. As we get stronger at these lifts, either by adding weight or eking out more repetitions per set, our forearms will grow steadily bigger.
Reverse Curls
The next part of building bigger forearms is training the brachioradialis muscles. People who train for strength generally do just fine here by including plenty of strapless barbell rowing in their routines. However, depending on which muscles are their limiting factors, they may still benefit from including some isolation lifts now and then.
If we look at our elbow flexors, we see that our biceps, brachialis, and brachioradialis muscles can help flex our arms. If you look at how they attach to our forearms, though, you’ll notice something interesting. The muscles in our upper arms—the biceps and brachialis—both have a good pull angle when our hands are facing upwards (as in the biceps curl and underhand chin-up). In contrast, our brachioradialis muscles twist around to the back, giving us a better line of pull if we use an overhand grip. As a result, the best way to isolate our brachioradialis muscles is to do reverse curls, like so:
The reverse curl is best done with a curl-bar (aka EZ-Bar), like so:
Most gyms will have a few of these, often with fixed weights. Even if you use a home gym, these are a good barbell to invest in. They’re great for rows, curls, triceps extensions, and pullovers. But if you don’t have a curl-bar, you can always use dumbbells instead.
If the reverse curl makes your elbows or forearms hurt, no problem, that’s a common issue—try hammer curls instead. Hammer curls use a mix of your brachialis and brachioradialis muscles, but they still do a good job of preventing your biceps from dominating the lift.
Wrist Curls
Wrist curls are the single best exercise for building bigger forearms. Your wrist flexors have great growth potential, and building them bigger can add inches to your forearms. They’re stimulated decently well with barbell curls, but to see a robust amount of growth, it can help to target them directly with wrist curls.
There are a couple of popular ways of doing wrist curls, but a good way to challenge them with a deep stretch and work them through a large range of motion is to use the seated wrist curl. And when doing the seated wrist curl, let the barbell roll down into your fingers, like so:
Many of our forearm flexors attach at the tips of our fingers, so by opening up our hands and then curling the weight back up with our fingers, we’re working them through a deeper range of motion. You’ll notice that if you do this, you’ll feel a much deeper stretch, get a much bigger pump, and get quite a bit more muscle growth out of your forearm curls.
Wrist Extensions
Wrist extensions are the best exercise for building bigger wrist extensors. Now, not everyone thinks this exercise is important. And to be fair. It’s not. It’s not so different from doing calf extensions in an attempt to bulk up the fronts of your shins. Is that something most people do? Nope.
Here’s the thing. If you have skinny forearms, they’re probably skinny from your wrists all the way up to your elbows. Most forearm exercises are good for training your forearms up near the elbows. That’s what barbell rows, reverse curls, and wrist curls will do. But they won’t make your wrists look thicker. And if you’re like me, with forearms that are 17 feet long, they won’t do much to bulk up the entire length of them.
That’s where wrist extensions come in. Our wrist extensors run along the entire backside of your forearms, adding girth along their entire length, right up to your wrists. These muscles aren’t big, and they won’t grow a tremendous amount, but since they span the length of your entire forearms, they can still improve the aesthetics of your forearms, making them look thicker overall.
You can do forearm extensions with a barbell or curl-bar, but it might be a bit heavy, especially for your thumb. You might need to start with the pink dumbbells or by holding some 5-pound weight plates, especially if you’re doing them for 15–30 reps.
The Two Forearm Workouts
There are two levels of forearm workouts. Level 1 is the minimalist approach, and it involves relying on compound lifts for forearm growth. It’s enough for a beginner to make steady progress, and it’s enough to maintain your forearm size once you’ve bulked them up. Level 2 is when you want to speed up your forearm growth by doing dedicated forearm training.
Forearm Workout: Level 1
As a skinny beginner, you can train your forearms with compound lifts. Rows will work your brachioradialis, biceps curls will work your wrist flexors, and lateral raises will work your wrist extensors. Now, are these lifts ideal for training your forearms? No. Your forearms are unlikely to be the limiting factor, they aren’t being worked through a large range of motion, and they aren’t being trained in a deep stretch. But since you’re a beginner, it’s not hard to provoke growth. It will be enough for now.
Plus, when you’re new to lifting weights, your hands can get pretty beat up. You aren’t used to holding dumbbells and barbells. They aren’t calloused yet. And so, if you start doing forearm isolation workouts, your grip and forearms might get so tired and sore that they limit your performance on the compound lifts, limiting your overall muscle growth. As a beginner, focus on getting stronger at the row, curl, and lateral raise.
A minimalist forearm workout looks like this:
- Barbell row: to bulk up your brachioradialis.
- Barbell curl: to bulk up your wrist flexors (isometrically)
- Lateral raise: to bulk up your wrist extensors (isometrically)
The next thing to remember is that maintaining muscle mass is much easier than building it. Once you’ve built bigger forearms with isolation lifts, you can maintain them with compound lifts. So spend a couple of months bulking up your forearms with isolation lifts, gain some size, and then cut them back out of your workouts, freeing up time and energy for other goals.
As a beginner, the bigger lifts are enough to build bigger forearms. Then, as a more experienced lifter, the bigger lifts are enough to maintain your forearm size and to make slow progress.
Forearm Workout: Level 2
After your first few months of training, you can radically accelerate your forearm growth by training them directly. You don’t need to do these workouts forever, just for a month or three. Then take a break, work on other goals, and focus on them again later if you need to.
Forearm workouts are fairly simple, and since your forearm muscles are relatively small, they won’t tax our cardiovascular system. As a result, they respond quite well to higher repetition and shorter rest times. That means that you can blast through an entire forearm workout in just 10–15 minutes, either on rest days or at the end of your regular workouts.
Here’s a short workout designed for maximal forearm growth:
- Reverse Curls: 2–3 sets of 10–15 reps.
- Seated Wrist Curls: 2–4 sets of 12–20 reps
- Seated Wrist Extensions: 2–3 sets of 15–30 reps
Take every set within a rep or so of muscle failure. It will burn with the fury of a fiery hell and give you a huge forearm pump. Every workout, try to eke out more reps or add a little bit more weight. If you’re new to training your forearms, expect rapid strength, both because your technique is improving and because you’re making newbie gains in your forearms.
Do this forearm workout 2–3 times per week, and do it for a minimum of 4 weeks, otherwise it might be hard to make lasting progress. And if you want to make your forearms significantly bigger, I’d recommend doing these workouts for 12 weeks. Feel free to swap in standing forearm curls and extensions, and maybe switch from reverse curls to hammer curls, or vice versa. That way you’re introducing some variety.
After training your forearms for 4–12 weeks, take a break for a month or ten, maintaining your forearm size with the bigger lifts. This will give your joints a break, and it should, in theory, re-sensitize your forearm muscles to dedicated forearm training.
As an intermediate lifter, you can build bigger forearms by training them directly. These dedicated forearm workouts will help you bulk them up quickly over the next 4–12 weeks. After that, you can maintain your forearm gains with compound lifts.
So, How Do You Build Bigger Forearms?
It’s common for skinny guys to have skinny forearms. Fortunately, there are plenty of common lifts that work our forearms at least a little bit, including rows, biceps curls, and lateral raises. As a beginner, that may even be enough for you to start gaining some forearm size.
But we can do much, much better than that. The best way to get bigger forearms is to train them directly, with forearm isolation lifts. So after you’ve gained your first 10–20 pounds of muscle, you can think about doing a couple of short forearm workouts every week. These workouts are simple and effective, and it’s realistic to gain a noticeable amount of size within just a couple of months.
- Reverse Curls: 2–3 sets of 10–15 reps to bulk up your brachioradialis.
- Seated Wrist Curls: 2–4 sets of 12–20 reps to bulk up your forearm flexors.
- Seated Wrist Extensions: 2–3 sets of 15–30 reps to bulk up your forearm extensors.
Ideally, you’d do these workout 2–3 times per week. You can do them on rest days, or you could tack them onto the ends of your regular workouts. The lifts are all simple, and although your forearms will burn with sadistic hellfire, they aren’t overly tiring, and they aren’t hard to recover from.
And, as always, if you want a full muscle-building routine, including a guide that covers everything you need to know about training, diet, and lifestyle, check out our Bony to Beastly Bulking Program (for skinny guys) or our Outlift Intermediate Bulking Program (for intermediate lifters). If you like our articles, you’d love our full programs.
Shane Duquette is the founder of Outlift, Bony to Beastly, and Bony to Bombshell, each with millions of readers. He's gained seventy pounds and has over a decade of experience helping more than ten thousand naturally thin people build muscle. He also has a degree in design, but those are inversely correlated with muscle growth.
Marco Walker-Ng is the founder and strength coach of Outlift, Bony to Beastly, and Bony to Bombshell. He's a certified trainer (PTS) and nutrition coach (PN) with a Bachelor's degree in Health Sciences (BHSc) from the University of Ottawa. He has over 15 years of experience helping people gain muscle and strength, with clients including college, professional, and Olympic athletes.
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I really appreciate this article. It’s nice to have a break down of the most important forearm muscles and exercise, especially for mass. I often see many videos talking about all the ways to hit them, but never articles that talk about the most bang for your buck. Thank you team, I really appreciate this 🙂
By the way, are you guys going to ever make an article on Blood flow restriction training?
Hey Vijay, thank you! Really glad you liked it.
Blood flow restriction training is really cool, and backed up by legitimate research. We use it in one of our arm training programs. We should write an article on it, too, you’re right 🙂
Thanks for replying Shane! Which arm training program are you talking about? I’m interested!
It’s a secondary program that we have for people who have finished the main Bony to Beastly Program. It’s not available outside of the member community yet. I need to make sure that it makes sense as a standalone program first. Right now, it’s sort of an expansion program. It assumes that you already know everything taught in the main program.
But if you’re still interested, you could email Sunny (us@bonytobeastly.com) and he can help you buy it. And when we update it for general release, you’ll get the update for free.
Thank you! 🙂
My pleasure, man 🙂
I’ve got a good one for forearms that kills two birds with one stone: the kettlebell bottoms-up press. It’s an incredibly difficult full-body exercise as well. Trying to hold a kettlebell upside down while moving it around is probably the biggest challenge of forearm strength I’ve come across. I’m not sure I’d recommend it to beginners, but it’s a great exercise to maintain forearm size and strength while also working the shoulders and core. It’s not cheating to use a little chalk.
That’s a great exercise for sure, and I’m a fan of it, especially for developing shoulder strength and stability. I’m not sure it’s a great hypertrophy lift, or a good exercise for building bigger forearms, given that our forearm strength won’t be the limiting factor and they aren’t worked through a deep range of motion, but you could be right that it’d help to maintain their size and strength afterwards.
And again, very cool exercise. I dig it.
Forearm training has been something i’ve kinda fell into in the last year and a half of training. I can safely say it has been some of the funnest training i’ve done in in a long time. I started initially with hypertrophy in mind but after a few weeks i fell into grip training, rock climbing and even armwrestling. There are so many fun ways to train forearms so my only advice to people would be to have fun with it. You can make great gains and dabble into different sports and training types you might never have tried before. Furthermore, the article was expertly written and i think for those with muscle hypertrophy in mind will get the results they’re chasing with these 3 exercises.
Hey Cole, thank you!
I agree with you. After a couple forearm workouts, after I got the hang of it, I really started to love it. I’m more familiar with the hypertrophy side of it, and even then, I’ve only done a few months of it, but it’s one of the more enjoyable muscle groups to train for sure. Armwrestling and rock climbing sounds like a blast. That’s sweet 🙂
Nice article and well timed as I was starting too look more at training forearms with isolation excercises.
I was curious at the average measurements as I seem to have a regular forearm size (11 something inches) but for me it’s really the wrists part/area that make my forearms look very skinny, so I was wondering if the exercises you shared are good for that as well, or if there are more specific exercises for that. Is that an area that is usually the very last part of the forearm that grows? (or is it just me)
Also the polish study, if I read well, studied the length of the forearms, not the circumference.. I think.. (I only read the summary).
Cheers!
Oh, wow, god, you’re right. I was looking for research on forearm circumference and that study popped up first, so when looking at the tables of measurements, I assumed they were talking about circumference. And since 10″ was a reasonable forearm circumference—mine started off smaller than that—I never thought to double check. I’ll fix that now. Thank you so much.
As for your question, you’re correct that most forearm training builds the muscles up near the elbows. Reverse curls and wrist curls won’t bulk up the entire length of your forearms. And those are the bigger muscles that are more popular to train. The good news is that wrist extensions DO train muscles that run the entire length of our forearms. They’re smaller muscles, analogous to the muscles on the front of your calves, but when you bulk them up, they’ll add a bit of size up near your wrists. When you try the exercise, you’ll get a pump there and you’ll see what I mean.
Damn… how do you actually measure forearms? In relaxed state, straight arm, I get a mere 8.5-inch circumference. But doing a Jamar dynamometer test, i can squeeze 65kgs cold (145lbs). And after weight training, it went up to 160lbs. Grip strength.
Hey Denis, a quick search tells me that on most men are only able to generate around 46kgs of force on a dynamometer. So you’ve definitely got a strong grip. That’s awesome.
The thing is, our grip muscles are located in our forearms, but they aren’t very big muscles. To build big forearms, we need to train the bigger muscles: our wrist flexors and brachioradialis (and you might want to train your wrist extensors, too). Reverse curls and wrist curls are great for that. And if you get strong at them, you can add inches to your forearm circumference.
8.5 inches isn’t all that big, but most of us have been there. I think mine started started off around there, but I only measured them after gaining my first 20 pounds, at which point they were at around 9–10″, if I recall correctly. And it wasn’t until I spent a few months training my forearms that they moved up to almost 13 inches.
Damn again. I measured my forearm today, after my first direct forearm workout (after some time). I realized my tape measure was off. Well, it was correct in cm, but the other side, which seemed like inch, was actually 3.3cm instead of 2.54cm. Some sort of Chinese inch? So my actual wrist size is 28cm, so 11 inch currently. What a relief. I will now vigorously do this workout 2 times per week and maybe increase to 3, if recovery will allow. Added to my regular workout. Thank you.
When taking measurements for biceps and forearms is the formula based on flexed or unflexed? Does it matter? Is there a best way to measure?
You’ll hear different opinions on whether we should be measuring our body parts flexed or relaxed. Depending on the person, flexing can add inches to the circumference. Fortunately, we’re getting these estimations from Dr Casey Butts, and he recommends flexing:
Biceps: flexed, at largest point
Forearms: fist clenched, hand out straight, measured at largest point.
Great article, I’ve never done direct work to my forearms, but I’ve measured them with my arm out straight and fist clenched. I got 14+ inch on my right arm and 13.5+ and my left arm. My wrist at 7 inches is small for my size (6’1.5, 225lbs). I’ve never done any direct arm work either. I only do 4 exercises being the parallel low bar squat, bench press, overhead press and deadlift (4 days a week, one lift per day). I’m going to start adding pendlay rows to my routine). I might try the exercises for the forearms like you mentioned in this article and the article on your outlift site. Keep up the great work and keep adding more articles to both sites as they are my favorite strength and training related sites.
That’s a cool workout routine, Damien. I like how simple it is.
Thank you so much!
Hey,
Jeff Cavaliere(Athlean-X) has explained in his videos that letting the weight roll into your fingers can cause elbow pain down the line. It can take months or even years to develop. What are your thoughts on that?
Jeff Cavaliere appears to be working very hard to make a video on every single lift to show that it’s DANGEROUS, we should STOP RIGHT NOW, and that it’s KILLING OUR GAINS. I don’t like the unfounded alarmism that he’s so infamous for. For more, we wrote a review for the Athlean-X bulking program for skinny guys.
So to answer your question more broadly, I’d watch other fitness channels to get a more evidence-based understanding of building muscle. Jeff Nippard, Omar Isuf, Jeremy Ethier, Renaissance Periodization, Barbell Medicine, and Alan Thrall are all awesome 🙂
But to answer your question more specifically, if rolling the weight down into your fingers isn’t causing joint to tendon pain, there’s no reason to think that it would result in injury down the line. Just follow generally good practices. Use reasonable training volumes, take a deload week every month or two, and listen to the signals your body is giving you. As a general rule of thumb, if a lift isn’t hurting your joints or tendons (in which case you can switch lifts or adjust your technique), then you’ll probably develop tougher joints, stronger muscles, and more robust tendons. Lifting doesn’t break us down, it builds us up.
Thanks for taking the time to write such a detailed answer. I appreciate it.
What do you think about Greg Doucette?
Is is it necessary to train the following forearm muscles or the above mentioned exercises already target them?
Wrist adductors, abductors
Wrist pronators and supinators
The US military does anthropometric studies on an array of different measurements. The last 2 studies were done in 1988 and 2012. The 2012 has a lot more obese representation which skews the data. But the one from 1988 is pretty good for getting an idea of different measurements regarding to arms, neck, calves, forearms, chest, shoulder, etc. In that study the average 20 year-old army soldier was about 5’9-5’10 weighed 75 kg (165 lbs) and had a forearm circumference of 30 cm (11.8 in) flexed (forearm makes 90 degree with upper arm, fist tightly closed, but palm facing you, or in other words fists is not bent towards you). If measured in the way that the 0.8 ratio you mentioned is usually measured (arms straight out with the fist bent and tight) you would probably lose 0.3-0.5 inches compared to the study. So I believe the average 20 year old that weighs 165 lbs probably has forearms somewhere around the 11.3-11.5 in. range. These studies are called ANSUR (1988) and ANSUR II (2012) the pdfs are free online, there is a website that took some measurements from ANSUR (1988) and created graphs where you can compared different datapoints based on measurements, the website title is “Anthropometric Measurements — an Intuitive Visualization”. You can also find spreadsheets from the ANSUR II from 2012 with all the data entries and use it to get an idea of different anthropometric measurements like average biacromial width by height, or wrist circumference vs forearm graphs. Anyways, I thought it could ge a good resource for the stuff you guys do here. Love your work Shane and I don’t know if your physique or graphic design art is more aesthetic, haha. Best wishes.
Thank you so much, Lucas! This is awesome 😀
Hey Shane,
You say somewhere on the site that you have a 6.5 inch wrist. Is this still true ? Can you tell if and how your wrist size has evolved going from 130 to 195 pounds? Also, if there has been an evolution, in your opinion how much of it is attributable to extra muscle / fat ?
Thanks a lot
Hey Vlad, right now I’m measuring my wrist at a hair under 6.75 inches in circumference. But did my wrist grow or did I just measure it slightly less accurately before? I’m not sure.
My bones have gotten quite harder since I started lifting and gaining weight. In my last DEXA scan, my bone density was off the chart. They’re heavier than they were before. I don’t think they’ve gotten much bigger, though. Not noticeably, anyway.
Hey, not sure if you’ve seen the adjustable forearm grippers, I believe you can adjust the weight from 0-90 pounds, but I was wondering if doing these can build some mass on the forearms or if they’re just strength oriented?
Hey Ryan, that’s a good question.
Forearm grippers are good for developing grip size and strength, but there’s more to our forearms than just our grip muscles. In fact, the biggest muscles in our forearms are our wrist flexors and elbow flexors. The wrist flexors on the inside of the forearm are best trained with wrist flexion (wrist curls). The elbow flexors are best trained with elbow flexion (reverse curls).
Our grip muscles can be bulked up, too, and forearm grippers are good for that, but those muscles are much smaller.
If building bigger forearms is a priority of yours, I’d use the forearm grippers in addition to the other exercises.