By: Igor Klibanov

As a fitness professional, you undoubtedly know how prevalent anxiety is, and you may even work with people who have it (heck, you might have it yourself). However, there’s very little specific information on how to make it better (other than “exercise is good for you”). And any improvements that come are simply a side effect of exercise. But what if there was a direct way to exercise specifically for anxiety reduction? What kind of impact would it have on your business?

Would you now be able to send a letter to your client’s doctor, explaining the scientific basis behind your recommendations? Would that help with medical referrals? Would you separate yourself from other trainers? Would you be able to carve a niche for yourself as the “mental health guru” of your community? I’ve done that, and you can too. So let’s jump in.

Do you have clients with anxiety? If so, you’ll want to read this article, because this is going to be the most thorough, detailed, and comprehensive article on the internet about how to exercise for people with anxiety.

We’ll leave no stone unturned. We are going to answer questions like:

  • What is anxiety? Seems like a silly question, but just so we’re all on the same page, and we’re working with the same definition, we’ll define it.
  • What is the optimal exercise protocol for anxiety? What works better – cardio or strength training? How long do you need to exercise for? How soon can you see anxiety-reducing results?
  • Do breathing exercise help reduce anxiety?
  • How does exercise work to reduce anxiety? What are the mechanisms?
  • What questions have yet to be answered? The whole field of “exercise as medicine” is still very new, and the research is just in its infancy.

So yes, today’s article will cover the anxiety side of mental health. And I know that there’s people probably wondering about depression. That will be covered in future articles. Stay tuned.

What is Anxiety?

What is it that differentiates plain old worry, from a clinical diagnosis of anxiety (or more accurately, Generalized Anxiety Disorder, or GAD)? According to the psychiatric diagnostic textbook, DSM-5, you have to meet certain criteria for a diagnosis of GAD. These criteria are:

  1. Excessive worry that lasts at least 6 months. By “excessive”, it is meant that the worry is disproportionate to the actual risk. Sometimes, this worry is generalized, and non-specific. There is no specific event causing worry. It’s a diffuse sense of worry. You can’t really pinpoint it like “if this problem was to go away, so would my worry.”
  2. It might be difficult to control the worry
  3. At least 3 of these symptoms must be experienced:
  • Edginess or restlessness
  • More tired than usual
  • Inability to concentrate
  • Irritability
  • Increased muscle soreness or pain
  • Difficulty sleeping (whether that’s falling asleep, or waking up throughout the night, or not feeling rested when you wake up)
  • Difficulty with daily functioning at work
  • Unrelated to other medical conditions
  • Unrelated to medications, drugs, or alcohol
  • Unrelated to another mental disorder

As you can see, there’s a very precise definition of GAD. And since it’s more of a cognitive thing, it’s not something you can look at blood and say “you have anxiety” in the same way that you can look at blood and say “you have high blood sugar.” Therefore, GAD is really diagnosed with and assessed with questionnaires. One of the most common questionnaires used for the assessment of anxiety is the State-Trait Anxiety Inventory (STAI).

So now that we’re all on the same page, and we have a standard definition of anxiety (I’ll be using “anxiety” and “GAD” interchangeably throughout this article), let’s start answering some of the most important questions about how to use exercise for anxiety reduction.

How to Exercise for Anxiety Reduction

Let me start this section off by saying that unfortunately, the research into what’s optimal is not as robust as I’d like it to be, and there are still a lot of unanswered questions. But in this section, I’ll summarize the available research on this topic.

Breathing, Yoga, Cardio or Strength Training?

Wouldn’t it be awesome if there was just a single study that did a head-to-head comparison of these 4 conditions, to really determine what’s best? Unfortunately, it doesn’t exist, so we’ll do the next best thing: look at the research that does exist.

In one study, researchers took 41 people with GAD, who have been on medications for at least 2 months, and for 4 weeks, they asked them to do one 2-hour breathing training per week (under supervision), in addition to daily 20-minute breathing practices, on their own.

The result: after 4 weeks, 73% of people had a reduction in their anxiety, and 41% of people actually went into remission.

Unfortunately, outside of that one study, I’m not aware of any others that either confirmed or refuted these results.

What about yoga? Yep, there’s research on that as well (although not a lot).

In one study, researchers took 69 participants, all of whom had GAD, and they did 10 days of intense yoga, followed by daily yoga practice for 30 minutes, for 6 months.

The result: there was a very large initial drop in anxiety, followed by a plateau (but not a rise). So yoga also seems like a promising treatment for anxiety.

In one study, 42 participants who did not have GAD, but were nonetheless assessed on an anxiety questionnaire were divided into 4 groups:

  • Group 1 had relatively low anxiety, and did cardio
  • Group 2 had relatively low anxiety, and did strength training
  • Group 3 had high anxiety, and did cardio
  • Group 4 had high anxiety, and did strength training

What do you think the results were?

The study lasted for 16 weeks, none of the groups had any reductions in anxiety for the first 8 weeks. The anxiety reductions came from weeks 8-16.

Both of the high-anxiety groups (groups 3 and 4) reduced their anxiety scores by a virtually equal amount (remember, anxiety is measured with the STAI questionnaire). The cardio group reduced it from 49.7 to 40.4. The strength training group reduced it from 47.6 to 38.5.

In the low-anxiety group that did strength training (group 2), they actually had no reductions in anxiety. But the low-anxiety group that did cardio (group 1) did have a small reduction in anxiety score (from 29.9 to 26.8).

So it would seem that for people with a lot of anxiety, there’s not much of a difference between strength training and cardio. However, to complicate matters, one study has slightly conflicting results (as frequently happens in scientific research).

In this study, 30 women with GAD and on medications for their anxiety were divided into 3 groups:

  • Group 1: strength training twice per week, lower body exercises only
  • Group 2: cardio twice per week (cycling)
  • Group 3: control group. They didn’t exercise.

After 6 weeks, 30% of the people in the group that didn’t exercise actually had a remission of their anxiety. Cool. I can just see the headlines now: “sit on your butt. Do nothing, and your anxiety will be relieved.”

But wait a minute. There’s more.

In group 2 (the cardio group), 40% experienced a remission of their anxiety.

In group 3 (the strength training group), 60% of experienced a remission of their anxiety.

So in this study, the clear winner was strength training. In the previous study, there was no clear winner.

One study found reductions in anxiety immediately after strength training, but anxiety levels rise back to baseline as early as 20 minutes after exercise. However, another study found that long-term strength training results in more stable reductions in anxiety (though unfortunately this study was not performed in people with GAD).

Sorry to confuse you with conflicting results. But towards the end of this article, I’ll help you figure out what’s best for each individual client.

So we know that there’s more than one way to “skin a cat.” A lot of different forms of exercise help with anxiety. But what about intensity? What’s the right intensity for anxiety relief? Fortunately, the research is much less conflicting on this issue.

One meta-analysis (which is a study that analyzes many other studies) found that a single bout of high-intensity strength training (over about 70% of 1RM) either has no change, or increase in anxiety. Whereas mostly moderate intensity (50-60% of 1RM) decreases anxiety. In One study, participants even saw reductions in anxiety at 10% intensity. But there aren’t any other studies that I’m aware of that attempt to answer the question of “what’s the lowest intensity that will produce reductions in anxiety?”

So now we know the intensity of exercise that’s necessary to reduce anxiety, but what about duration? How long do you need to exercise? Most studies that show reductions in anxiety use exercise protocols that are in the 40-60 minute range, but that’s more incidental. That’s simply how long it takes to complete the amount of exercise that participants have to do.

But what’s the minimum required to reduce anxiety? One study looked at exercise durations of as little as 6-8 minutes, 5 times per week. Unfortunately, after 15 weeks of this, there were no reductions in anxiety. So 6-8 minutes is not enough.

However, in another study, people exercised for 20 minutes, 3 times per week, for 16 weeks, and in as little time as that, yes, anxiety was reduced.

In terms of the number of weeks required, there’s no surprises there. One meta-analysis found that exercise programs over 16 weeks have the greatest anxiety-reducing effects. Programs between 10 and 15 weeks have medium effects, and programs under 10 weeks have small effects. So now you know that if you want to run an “anxiety buster” program, you have to sell packages of at least 16 weeks. There’s your business tip for the day 😉

And what about frequency? One meta-analysis found that 3-4 days per week of exercise produces greater anxiety reductions than both higher and lower frequencies. An example of a case when “more is not better.”

So now, we have a fairly precise idea of the type, intensity, duration and frequency to use when trying to exercise for anxiety reduction.

How Does Exercise Compare to Other Therapies?

One meta-analysis that looked at 6 different studies noted that “Importantly, we have found a moderate effect (SMD =−0.58) on anxiety symptoms reductions, which is of similar magnitude of the anxioloytic effects from common pharmacotherapy such as paroxetine (SMD=−0.56), flouxetine (SMD=−0.56), quetiapine (SMD=−0.56), fluvoxamine (SMD=−0.60) and venlafaxine (SMD=−0.50) in people with anxiety disorders.

This isn’t an either/or type of scenario here, and it doesn’t mean that you shouldn’t use anti-anxiety medications. It simply means that you should be aware of the anxiety-reducing effects of both.

Why Does Exercise Work?

We know that exercise works. Although there’s debate about what works best, there’s very little debate that it works. But the geeks among us (like me) want to take things one step further, and figure out why it works.

There are a number of theories on it. One theory about how exercise reduces anxiety is the distraction hypothesis. Simply put, if you’re focusing on one thing, it provides a distraction from whatever is causing the anxiety. If you’re breathing hard from exercising, you focus on the workout, and temporarily forget about what’s causing the anxiety.

Another theory is the serotonin hypothesis. Serotonin is a neurotransmitter (brain chemical) that makes you feel content and relaxed. In people with anxiety, there is less serotonin in the brain, and exercise facilitates the production of serotonin.

Angela Clow and Sarah Edmunds, the authors of the book Physical Activity and Mental Health also propose a couple of other hypotheses.

For one, they propose that exercise affects our brain waves. There are 4 different kinds of brain waves that are produced based on what state you are in. Beta waves are the waves we normally produce when we are awake and alert. Alpha waves are the waves we normally produce when we are deeply relaxed. Like in those moments when you’re lying in bed, and you’re not quite asleep, but not quite awake, either. And then, there are delta and theta waves, which are during early sleep and during deep sleep, respectively. In people with anxiety, there aren’t enough alpha waves, and exercise helps with that.

Another theory by Clow and Edmunds is that exercise raises the threshold at which anxiety is felt. There’s always some physical arousal, ranging from virtually none (as in deep relaxation or sleep), to a lot. In people with anxiety, the amount of physical arousal required for them to classify that as “anxiety” is lower than in people who don’t have anxiety. Exercise helps raise that threshold.

As you can see, there are a number of ways that exercise for anxiety reduction works. 

Unanswered Questions

As mentioned a number of times throughout this article, the whole field of “exercise as medicine” is still only in its infancy, and particularly with anxiety, there are still a lot of questions that the research hasn’t yet gotten around to answering. Things that I would like to know are:

  • What’s the minimum “dose” of exercise required to have anxiety-reducing effects?
  • What’s the optimum “dose”?
  • Is there a best “form” of exercise? Is cycling superior to swimming, vs. running, vs. aerobics classes, vs. lifting weights?
  • Are there differences between men and women?
  • Are there differences between young and the elderly?
  • Exercise isn’t effective in everyone. How can we predict in whom exercise will not have anxiety-reducing effects?
  • What happens when you combine cardio and strength training? Do you get stronger anxiety-reducing effects? In theory, that might be the case, but in practice, it’s not. Sometimes, the effects might be lower than either one by themselves, or they might be more than the expected combined value of each one. For example, it might be a 1 + 1 = 3 type of scenario.

… and lots of other questions.

What Works For Your Clients?

You’ve just seen a bunch of studies on the topic of exercise and anxiety, but much of it is conflicting, and you might be more confused than clear. So let’s end the confusion, and help you figure out what works for your clients, specifically.

As I mention in my article on the importance of measurements, it’s measuring your clients’ results that helps you individualize, and tailor your approach. After all, what works for one person may not work for another.

So as it pertains to anxiety, search online for an “anxiety questionnaire.” Have your client fill it out. Then get them exercising on whatever kind of program you want. Strength training, cardio, yoga, anything. Then, after one month, take the same questionnaire again. If their score improved, you know you found something that works (assuming no other changes in medication, diet, etc.). If their score didn’t improve, try something else. Either a different type of exercise, or a higher intensity, or a lower intensity, etc.

Or, if you want to see the immediate effects of a single workout, what I do with my clients, is I have them fill out a very quick questionnaire before the workout, and immediately after. Here’s what the questionnaire looks like:

Rate these feelings on a 0-5 scale as you’re feeling right before a workout (0: I don’t feel this at all; 5: I feel this very intensely):

Anger:              0 1 2 3 4 5
Confusion:      0 1 2 3 4 5
Sadness:          0 1 2 3 4 5
Vigor:               0 1 2 3 4 5
Fatigue:           0 1 2 3 4 5

If the post-workout ratings are better than the pre-workout ratings, we have an effective program. If the post-workout ratings are worse than pre-workout, I would try a different program. I would get the client’s input on what caused the decrease in scores, and make adjustments based on that. If there’s no clear/concrete answers, the first variable I would tweak would be the intensity. I’d use a lower percentage of 1RM, and take longer breaks in between sets. Or alternate a strength exercise with a stretch/mobility drill.