New Data On Physical Activity As An Antidote To Depression

Susan Krauss Whitbourne

When you wake up and begin to plan your day, how much do you factor in time for exercise? Perhaps you’re saddled with obligations, not only for work, but also for childcare, housekeeping, and/or the many little nuisances that can invade your waking hours. A dedicated time for physical activity seems like a luxury that you might get around to at the end of the day, maybe.

You know that logically you should exercise and that there are myriad benefits to putting your body through various forms of being in motion. You’re not happy with yourself for not finding time for it in your schedule, but you feel you have no choice.

As stressed and frantic as you feel at times about your hectic life, has it ever occurred to you that exercise could do more than build your bodily strength and vitality? Could it be worth carving out those chunks of time to get up and move?

PHYSICAL ACTIVITY AND MENTAL HEALTH

According to Central China Normal University’s Fei Tian and colleagues (2024), there is reason to believe that physical activity could indeed play an important role in combatting not only the development of chronic health problems but also depression. Prior research supporting this possibility used observational methods to show an overall association between physical activity and depression but failed to zoom in on the precise nature of this relationship. What was lacking was the demonstration that changes in physical activity could be linked with changes in depressive symptoms. Furthermore, these studies failed to control for initial levels of depressive symptoms in the samples. They also did not sufficiently represent low- and middle-income countries, limiting the generalizability of the findings.

Before turning to the details of the Chinese study, it’s a good idea to take a step back and try to understand why exercise could have this beneficial effect. The authors did not specifically address this issue, but there is ample evidence in the research literature to suggest several possible mechanisms. Physiologically, exercise creates its own internal set of mood boosters by activating some “happy” neurotransmitters, which induces a natural high. Psychologically, as you move your body, you also gain a sense of competence and efficacy. Maybe you thought you couldn’t do that deadlift with more weight than you used in the past, but, surprisingly enough, you did. Practicing yoga and flexibility exercises can also alleviate joint pain while also helping you establish a connection with your body’s inner workings.

Evidence for the effectiveness of exercise as an alternative treatment for depression has accumulated over the past 30 years. However, it has been slow to catch on compared to the focus in the mental health literature on medications and psychotherapy. The Tian et al. study therefore could provide important new data to refocus attention on physical activity’s benefits in its own right.

TESTING THE PHYSICAL ACTIVITYDEPRESSION RELATIONSHIP

Using the Chinese Family Panel Survey (CFPS), the research team had access to longitudinal data from a nationally representative sample of 7,633 adults studied over the years of 2016 to 2020. Through online survey software, the participants reported over the course of three test occasions on their depressive symptoms and two on their engagement in physical activity (frequency and duration). The tracking over time allowed Tian and colleagues to estimate the effects of changes in activity as they corresponded to changes in depressive symptoms.

The findings supported the study’s prediction not only that regular participation in exercise would be related to lower depression scores but also that people who ceased physical activity were more likely to develop depression across the years from 2016 to 2020. Unlike previous researchers, the author team eliminated participants with baseline depressive symptoms, wiping out the possibility of “reverse causation” of depressive symptoms on fluctuations in activity.

Over the course of the study, 20 percent of participants developed significant depressive symptoms. However, these rates varied by physical activity fluctuations with those who persisted in the same levels of activity over time less likely to develop symptoms (16 percent) compared to those who infrequently exercised (22 percent). These differences were maintained after the researchers controlled for demographic factors as well as health status and lifestyle, but, additionally, with these controls in place, the authors found higher rates of depressive symptoms developing in those who ceased physical activity altogether.

As the authors concluded, “These findings suggested that persistent participation in regular physical activity (PA) may have a protective effect against the incidence of depressive symptoms.” Importantly, the intensity of activity didn’t seem to matter as much as did persistence: “adults who engage in even low-intensity regular PA, such as walking or jogging, will have a notable antidepressant effect as long as they persist.”

TURNING ON YOUR OWN MOOD BOOSTERS

The moral of the story from this large and well-controlled study is that persistence matters when it comes to boosting your mood through exercise. The authors also supported the position from prior work in the mood-exercise link that by moving your body, you can feel better about yourself, both in terms of your sense of self-esteem and feelings of self-efficacy. Exercise has the additional advantage of bringing you into contact with other people, expanding your social support network as well as just plain socializing. From an overall health perspective, when you exercise, you are healthier, and so are better able to withstand some of the stresses that could come from the development of a chronic disease such as hypertension or reduced mobility.

Alright, you say, “I promise I will start to exercise. Really!” How can you turn this vague assertion into action? Based on the study’s findings, your commitment has to begin with an exercise program you can maintain. Gym owners are all too familiar with the January surge in memberships, which eventually falls off in the ensuing weeks. You need to avoid becoming one of those casualties.

Because exercise can be moderate, as Than et al. showed, making a decision as simple as not taking the elevator when you could take the stairs, not parking as close as you can when you’re out shopping, or not taking public transportation to the stop nearest your destination. If your mobility is limited, you can get your exercise minutes in by stretching, working on your balance, or doing chair exercises with weights. The regular physical activity in the Chinese study amounted to 30 minutes a day for at least three days a week. Although more is generally better according to the Centers for Disease Control and Prevention guidelines, anything is better than zero. Surely you can take a half hour every other day to devote to some form of exercise.

To sum up, it may seem like an impossibility for you to become a regular exerciser, but by making the commitment for this hour and a half a week (and maybe more), you can lessen the time and effort needed to alleviate the stress associated with your day-today life. Fulfilling your body’s need to move can, in time, fulfill your mind’s ability to free itself of those stresses.