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Many people believe they aren’t building muscle or losing fat because their hormones are cream-crackered.
This is particularly true among 40+ weightlifters, who think that Father Time sends their hormones so skew-whiff that they have no chance of building a body that looks good and functions well.
Here’s the truth: your hormones play a role in muscle growth and fat loss, but they aren’t the be-all, end-all of health and body composition.
Provided you exercise regularly, eat a healthy diet, and rest adequately, you can drastically improve your hormone profile and body composition, regardless of your age.
In this article, you’ll learn how to manage your hormones as you age to maintain a lean, healthy, and muscular body well into your golden years.
How to Improve Your Hormone Levels As You Age
The primary hormones that affect your body composition are insulin, leptin, ghrelin, growth hormone, and the sex hormones testosterone and estrogen.
As you age, your body produces more or less of these hormones and changes how it interacts with them.
If left unchecked, these hormonal fluctuations alter your body composition for the worse, eventually leading to impaired mobility, increased morbidity and mortality, and lower quality of life.
Fortunately, you aren’t entirely under the heel of your hormones. With the right interventions, you can greatly reduce the impact your hormones have on your body composition and health as you get older.
The most important thing to understand about hormones is that they’re essentially messages your body uses to tell various organs what to do, and your behaviors are the single most important factor that determines what these messages say.
For example, if you’re sedentary and eat too many calories, your hormones send very different messages (gain fat, mainly) than if you’re active and eat the right number of calories for your body (burn fat, largely). When you lift weights, your hormones tell your muscles to grow bigger and stronger posthaste, and when you do lots of cardio, your hormones tell your mitochondria to become more efficient at processing oxygen and producing energy.
Thus, when people blame hormones for fat gain, muscle loss, poor recovery, or some other malady, they’re barking up the wrong tree. Your hormones are the mail, but your behaviors write the message.
All of that said, it’s undeniable that age does affect your hormones, body composition, and fitness to an extent, but it’s much less of a factor than most people realize.
Here’s how to optimize six of your body’s most important hormones.
Insulin
Insulin’s main function is to regulate the amount of glucose (sugar) in your blood.
As you become older, the insulin level in your blood increases and your insulin sensitivity decreases. This double whammy makes you more inclined to store any excess calories that you consume as fat (particularly abdominal fat).
Multiple studies show that lowering your body fat percentage with a mix of strength training and dieting is one of the best ways to increase insulin sensitivity, even when you’re middle-aged or older.
(And if you’d like to know exactly what diet to follow to lose weight as quickly and healthily as possible, take the Legion Diet Quiz and in less than a minute, you’ll know exactly what diet is right for you. Click here to check it out.)
For example, in one study conducted by scientists at the University of Maryland School of Medicine, 35 men aged between 52 and 68 years old followed a calorie-controlled diet for 9 months with the intention of losing 0.5-to-1 pounds of body weight per week.
At the end of the study, the men had lost an average of ~20 pounds each, reduced their body fat percentage by an average of 6%, and significantly improved their insulin sensitivity (9 of the men reversed prediabetes).
In other words, if you stay active and manage your diet properly, you can improve your insulin sensitivity so much that it’s significantly better than that of people half your age. An active, lean person in their 60s could have much better insulin sensitivity than a sedentary, overweight 20-something.
Leptin
Leptin is produced by fat cells and regulates hunger, metabolic rate, appetite, motivation, immunity, fertility, and libido.
It’s also heavily involved in maintaining body weight because it tells your brain that you have enough energy stored in your fat cells and that your body can expend energy, eat, and engage in normal physical activity.
(Check out this article if you’d like a full rundown on how leptin affects weight loss.)
As we age, we become less sensitive to leptin, making it easier to overeat, burn less energy, and gain fat over time.
Studies show that taking regular exercises—whether that’s strength training, cardio, or a mix of the two—effectively improves circulating leptin levels and leptin sensitivity in middle-aged or older adults.
(And if you need help deciding which training program to follow to reach your health and fitness goals, take the Legion Strength Training Quiz, and in less than a minute, you’ll know the perfect strength training program for you. Click here to check it out.)
Ghrelin
Ghrelin, sometimes referred to as the “hunger hormone,” is produced in your gut. It’s involved in many bodily processes associated with your sleep-wake cycle, perception of pleasure, taste, and fat storage, but its primary function is to stimulate your appetite.
Most studies show that levels of ghrelin decline as we age.
“Good!” you’re probably thinking. “Won’t that help me lose weight?”
Yes, but not necessarily in a good way. Declining appetite in older folks is often associated with muscle wasting and frailty, partly because they eat very little protein. What’s more, ghrelin stimulates growth hormone secretion, which is why low levels of growth hormone are associated with an increased risk of sarcopenia (age-related muscle loss).
This is undesirable because retaining muscle as you age is one of the best ways to maintain sound metabolic health.
The best way to increase ghrelin levels for most people is to do high-intensity cardio, but this isn’t always practical and doesn’t offer all of the benefits of strength training.
Fortunately, research shows that lower-intensity exercise and weightlifting also substantially boost ghrelin levels in older adults (including postmenopausal women).
For example, in one study conducted by scientists at the University of Texas Medical Branch at Galveston, researchers found that participants who were ~70 years old and who did a combination of 20 minutes of treadmill walking and a couple of sets of resistance exercises (such as leg press, chest press, seated row, leg extension) 3 days per week, increased ghrelin levels by 47% in 12 weeks.
Growth Hormone
Growth hormone (GH), or somatotropin, stimulates cell growth and replication.
As we’ve already seen, GH levels decrease when ghrelin decreases, though GH levels also decline irrespective of ghrelin. This is associated with several adverse effects, including loss of vitality, mobility, and mental acuity and increased frailty and cardiovascular issues.
It also causes muscle loss and fat gain.
As young adults, we can increase GH by exercising. The higher the intensity of that exercise, the more GH levels will rise.
This diminishes as we get older, though, and while there doesn’t appear to be much we can do about this, we can largely mitigate the downsides of low GH levels.
For instance, research shows that GH levels are significantly higher in lean elderly than overweight elderly people following aerobic exercise. Thus, maintaining a healthy body fat percentage as we age will help us maintain considerably higher levels of GH. (Remember what I said earlier about our behaviors driving our hormones? GH levels are a prime example.)
What’s more, you can still build muscle, gain strength, and lose fat with the right diet and exercise program even if your GH levels don’t jump as much as they used to after training or dip a bit as you age. In other words, GH isn’t as central to fitness as other hormones, such as testosterone.
(And again, if you’d like specific advice about which training program you should follow to reach your health and fitness goals, take the Legion Strength Training Quiz.)
Testosterone
Testosterone is a steroid hormone that stimulates the development of male secondary sexual characteristics such as increased body hair, muscle mass, and bone density. It’s produced mainly in the testes in men and the ovaries in women.
Testosterone is highest in males during their teens and twenties. Thereafter, levels decline slowly at about 1% per year (in most people—it’s not clear if this is true in folks who stay lean and active).
Testosterone plays a key role in muscle building, muscle strength, and fat loss, which is why research shows that declining testosterone levels are associated with decreased muscle mass and strength and increased fat mass (especially in the form of visceral fat).
Most people think that aging is solely responsible for declining testosterone levels, but this isn’t necessarily true.
Research shows that lifestyle factors are equally, if not more, causative than aging itself. For example, here’s a short list of the most significant lifestyle factors that can depress testosterone levels:
In other words, testosterone doesn’t automatically “bottom out” because you age. If you’re proactive, you can maintain very healthy “T” levels as you get older, with the most effective ways being staying lean, weightlifting regularly, managing stress, eating a balanced diet, and maintaining good sleep hygiene.
What’s more, you don’t need stellar testosterone levels to get into great shape. The natural variance in people’s anabolic hormone levels just doesn’t influence muscle building and fat loss nearly as much as some people want you to believe. Specifically, even if your testosterone levels sag slightly as you get older, you won’t notice much of any decline in strength, muscle gain, or vitality so long as they’re still within a healthy range.
Estrogen
Estrogen is the sex hormone responsible for developing and regulating the female reproductive system and secondary sex characteristics. While estrogen does affect male health, fitness, and energy levels (it’s actually quite important for muscle growth), it’s more central to women’s well-being.
Like testosterone, estrogen plays a crucial role in building muscle and losing fat. Specifically, it . . .
- Improves insulin sensitivity and stabilizes blood sugar levels.
- Reduces fat storage in the lower body and abdomen and increases concentrations of a compound called AMP-activated protein kinase (AMPK), which boosts fat burning throughout the body.
- Boosts muscle growth and recovery and decreases muscle soreness after weightlifting.
Estrogen levels fluctuate each month and across a female’s lifetime.
During menopause—around the age of 50 for most women—estrogen levels drop dramatically (as do progesterone, testosterone, follicle-stimulating hormone, and luteinizing hormone), which . . .
Similar to testosterone in men, you don’t need high estrogen levels to improve body composition. Several studies show that you can build muscle and lose fat despite dwindling estrogen levels after menopause.
In one study conducted by scientists at the State University of Campinas, postmenopausal participants increased muscle mass by around 2.5%, decreased body fat percentage by almost 7%, and greatly increased leg strength (41%) and bench press strength (27%) after just 16 weeks of training 3 times per week.
At bottom, women can look at estrogen the way men look at testosterone. Yes, it’s a pivot of your health and fitness, but you can maintain healthy levels through diet, exercise, and other habits, and a small decline is benign.
Conclusion
Hormone levels change as you age, and if you do nothing to curb their decline, they can play mischief with your body composition and health. Fortunately, maintaining a healthy weight and doing regular exercise goes a long way to redressing the balance.
There are hormones, such as growth hormone, testosterone, and estrogen, that decrease regardless of how we manage our weight or what we do with our diet and training regimen.
This doesn’t mean you’re destined to become frail, fat, and unhealthy in later life, though. Levels of these hormones don’t need to be sky-high to have a fit and healthy body, and you can maintain perfectly adequate hormone levels with the right diet and exercise regimen.
Specifically, if you want to gain muscle and strength, lose fat, and stay healthy when these hormones are in short supply, you’ll need to manage your calorie and macronutrient intake and training and recovery more closely.
If you want a fitness program that does just that and that’s specifically designed to help absolute beginners at any age and fitness level get in the best shape of their life, check out my newest fitness book for men and women, Muscle for Life.
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