Some people are born with naturally thin frames and the metabolism that allows them to eat whatever they want and never gain weight. It’s tempting for these people to forego exercise altogether in favor of hanging on the couch and watching TV with a friend. As a certified personal trainer, I’ve had many clients who weren’t convinced they actually needed to exercise since they were naturally thin. Exercise does a lot more than help us burn calories to lose weight. In fact, not getting enough exercise can have a pretty significant impact on what’s going on in our bodies and the future of our health. What really happens when you don’t exercise enough?
You could get injured
I’ve told clients before that they should think of exercise and fitness as a use it or lose it situation. The more you use your body, the more accustomed it is to movement and the more it can deal with before it becomes fatigued. When you don’t exercise, though, your muscles become deconditioned. What this means is that when you are sedentary, the result is a partial or complete reversal of any prior gains in strength, cardiovascular fitness, and flexibility or mobility.
One consequence of these losses in physical fitness can be injury. Have you ever sprinted for the bus after weeks of inactivity only to strain a muscle? That’s deconditioning at work. Or maybe you’ve tried to pick up something heavy (that you used to be able to lift without any problem) and threw your back out or strained your neck. You guessed it, deconditioning. In order to keep your body moving the way it was designed and injury-free, getting enough exercise is key. Maybe you didn’t get injured, but are you starting to have more aches and pains? Deconditioning has also been associated with chronic low back pain. So if you’re starting to notice a few more aches and a bit more stiffness when you wake up in the morning, it may be time to use it or lose it.
You get grumpy and depressed
If you haven’t been exercising enough and you notice you’re feeling grumpier or sadder than usual, it isn’t all in your head. When it comes to your mood, regular exercise can be a huge factor. For those individuals with clinically diagnosed depression, exercise can lead to a reduction in symptoms. The benefits of exercise are not significantly different (better or worse) from those garnered from cognitive therapy or antidepressants and has been suggested as an adjunct to these types of treatment. You don’t need a diagnosed mental illness to reap the benefits of exercise on mood though. Research has shown that people with non-clinical levels of depression and anxiety also benefit from regular exercise.
Those who exercise regularly and then stop or significantly decrease their exercise also see a difference in mood. Have you ever met someone who is training for a marathon and then gets very sad or grumpy when it comes time to taper? Some scientists argue that this is because exercise has an effect on neurotransmitters like serotonin and dopamine levels in the brain, which can help make us feel happy. For people who exercise a lot and then stop, it can almost be like going through withdrawal from a drug. A positive mood is quite a powerful thing. It’s also important to note that as long as you’re exercising regularly, it doesn’t much matter exactly what you’re doing. Research has found that improvements in mood and general well-being persist with regular exercise, regardless of whether the exercise was high intensity or low intensity. This means that you don’t have to start running marathons or going to CrossFit to see an improvement in mood, you just need to move.
You feel more stressed
If you’ve ever had a friend talk about going to the gym to blow off steam, she isn’t totally off base. Most Americans say they experience stress in their daily lives, with 40 percent saying they experience stress frequently and 36 percent saying they sometimes experience stress. This is important because stress, for which symptoms include increased heart rate and muscle tension, is associated with higher blood pressure, which may lead to heart disease. When your friend says she feels less stressed after spending an hour in spin class or taking a few hits on the heavy bag in a boxing class, she isn’t imagining it, but just one class may not make that much of a difference long-term. Both inflammation and oxidative stress have been shown to be important in the development of psychological stress and anxiety. Regular exercise serves as an anti-inflammatory that can help reduce this oxidative stress, thereby reducing psychological stress. In this case, the amount of exercise matters somewhat.
In a study comparing inactive women, moderate exercisers (two-six hours of exercise per week) and vigorous exercisers (more than six hours of per week), researchers found that women who exercised regularly experienced a smaller response to stress. The response to an external stressor produced by the researches was measured both physiologically (through heart rate and cortisol levels) and psychologically (measured by chronic stress and state-trait anxiety levels). Before being exposed to the stressor, the groups of women did not vary in terms of stress level. After stress exposure, non-exercisers showed a higher stress response measured by change in heart rate and self-reported stress than the two exercise groups. Moderate and vigorous exercisers showed lower responses to stress, with vigorous exercisers having a slight edge over moderate exercisers. So while your friend who is at the gym for two hours every day may be cool as a cucumber, spending even 30-45 minutes at the gym every day can help with how your body responds to stress.
Your bones get weak
In my experience as a trainer, many women who do exercise stick primarily to cardio training like running or taking a spin class because they think it’s the best type of exercise for their health. While cardio training is important for your heart and is part of the recommendations set by the American College of Sports Medicine (ACSM), it isn’t the only type of exercise you should be doing. In fact, resistance training, like lifting weights or doing bodyweight exercises, may be one of the most beneficial types of exercise for women in particular. As we age, our bones get weaker. This is especially true of women who are four times as likely as men to suffer from osteoporosis, which is a bone disease that occurs when the body loses too much bone, makes too little bone, or both. Individuals who have less bone mass to begin with are at a higher risk of developing osteoporosis.
So what does this have to do with exercise? Research has consistently shown that resistance training has a positive effect on bone mineral density in women. By engaging in resistance training before menopause, a woman will increase her bone mass and reduce her risk of developing osteoporosis. For those who are already postmenopausal, strength training is still shown to be more effective for increasing bone mass than non-weight bearing cardiovascular exercise. The ACSM recommends that adults train each major muscle group two or three days each week using a variety of exercises and equipment. If you don’t get enough regular exercise, and that includes resistance training too ladies, you may be putting your bones at risk.