While the current Physical Activity Guidelines suggest that adults should exercise 150 minutes per week, a 2018 study found that inactive persons who exercised 60 minutes per day, five days a week, burned 3,000 calories per week and lost weight, while those who exercised only half as often did not. You can work up to 60 minutes every day even if you’re a newbie! This might be as simple as taking a short stroll after each meal or discovering a new sport you enjoy, such as strength training, swimming, or cycling.

1. Muscle Loss as People Get Older
After the age of 30, our lean muscle mass naturally declines by 3 to 8% per decade, a condition known as sarcopenia. You may also lose muscle if you’re less active due to age-related health concerns like arthritis, or if you’ve stopped being active for several days due to an injury or surgery.

Fat burns less calories than lean muscle. So, unless you’re doing weights on a regular basis to maintain and build muscle, your body will require less calories each day. If you continue to consume the same number of calories that you did when you were younger, you will accumulate weight. Also, most people continue to eat the same quantity of food, but because they have less muscle mass and less exercise, causing them to gain unnecessary weight over time.

2. Hormonal Changes That Are Normal
According to the CDC, middle age is the general time to gain weight. Menopause, which typically occurs between the ages of 45 and 55 in women, results in a considerable decline in estrogen, which encourages excess pounds to accumulate around the belly.

This change in fat storage could accelerate extra weight gain and raise the risk of high blood pressure, heart disease, high cholesterol, and type 2 diabetes.

Changes in estrogen levels during perimenopause (the years leading up to menopause) can create mood swings that make sticking to a healthy diet and activity plan more challenging. According to UC San Diego Health, the average weight gain during the transition to menopause is roughly five pounds. 

Men, on the other hand, see a considerable reduction in testosterone as they age – diminishing at a rate of around 1% to 2% each year around the age of 40, according to Harvard Health. Testosterone is in charge of controlling fat distribution, muscular strength, and bulk, among other things.

According to Harvard Health, the pituitary gland’s synthesis of growth hormone (GH) decreases as people become older. Building and maintaining muscle mass is one of GH’s many activities. As GH levels drop, it becomes more difficult for your body to build and retain muscle, which has an influence on how many calories you burn.

3. Your Metabolism Is Slower Than It Was Previously
Your metabolism, a complicated mechanism that transforms calories into energy, is likely to slow as your muscle mass declines. Calorie burning is reduced when there is more fat and less muscle. Furthermore, as people age, they become less active, which decreases their metabolism.

4. You’ve Become More Sedentary And Stressed
Your career is likely to be very established by the time you reach your forties and fifties, which, although excellent, might provide some weight reduction issues. For starters, you’re probably moving less.

You may drive an hour or more to and from work, sit at a desk for eight or more hours a day, and have so much on your plate that you don’t have time to walk or exercise throughout the workday.

You could also be too busy to take a break for lunch, increasing the chances that you’ll eat something unhealthy to satisfy your appetite.

5. Significant Lifestyle Changes
Some of the causes of middle-age weight increase have nothing to do with what’s going on inside your body and everything to do with how life evolves.  Suddenly, the hour you spent after work at the gym is spent at home with your kid. Later, your child’s after-school time is taken up with playdates, schoolwork, and other activities that demand your attention, depriving you of personal time.