The truth is in the pudding: Mobility and muscle performance decline with age. One study found that muscle force and power decrease by up to 49 percent between the ages of 25  and 75. Data also shows that adults over 40 can experience a 1 to 2 percent decline in lean body mass and a 1.5 to 5 percent decline in muscle strength per year.

In a new study, researchers claim that belly fat (specifically, your waist and hip circumferences) can be a key indicator of future mobility and strength performance.

RELATED: 10 Best Ways to Strip Away Your Unhealthiest Belly Fat, According to Doctors.

Larger waistlines are associated with weak mobility.

A new study published in the journal Aging found that larger waist-to-hip and waist-to-height ratios can significantly slow down physical performance. To arrive at their findings, researchers put over 10,000 people through a simple strength and mobility test.

“By assessing waist-to-hip ratio and waist-to-height ratio, healthcare practitioners can identify individuals at greater risk of these health complications and implement targeted interventions to mitigate risks and improve long-term health prospects,” wrote the authors.

The study used two metrics to assess body composition: waist-to-hip ratio and waist-to-height ratio. 

The researchers used the waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) to measure participants’ body composition.

To get waist circumference, they measured “at the narrowest point between the ribs and hips.” Hip circumference refers to the “widest part of the buttocks.”

The WHR is calculated by dividing the waist circumference by the hip circumference. WHR is recognized by health experts as “an indicator of central adiposity and fat distribution,” according to the study. An “elevated” WHR has been linked to an increased risk of cardiovascular diseases, metabolic disorders, and prediabetes.

Meanwhile, the WHtR is calculated by dividing the waist circumference by height. This ratio “offers a direct and efficient assessment of an individual’s health risks associated with abdominal fat,” including cardiovascular diseases and diabetes.

A normal WHR is a value below .90 for men and .85 for women, respectively. A WHtR value below 0.5 for both men and women is “indicative of a more favorable distribution of body fat.”

RELATED: Scientists Just Figured Out Why You Can’t Get Rid of That Stubborn Belly Fat.

Abnormal wait and hip circumferences were linked to poor physical performance.

The study included 10,934 adults who were picked at random. Prior to WHR and WHtR calculations, the researchers assessed blood pressure, weight, height, cholesterol levels, and glucose levels, and gathered data pertaining to certain lifestyle habits (smoking, diet, and exercise).

WHR and WHtR values were consistently healthier among women than men. However, overall ratios were alarmingly high. Their findings were as follows:

61 percent of men had abnormal WHR values

39 percent of women had abnormal WHR values

71 percent of men had abnormal WHtR values

53 percent of women had abnormal WHtR values

Next, the scientists measured individuals’ physical performance via a simple chair test. The instructions were clear and concise: With your arms crossed over your chest, stand up from a chair, then sit back down. Do this five times as fast as you can.

Overall, the men performed faster. They averaged 7.6 seconds, while the women averaged 7.9 seconds.

Another analysis compared performance times between normal and abnormal WHR and WHtR ratios. Here’s what they found:

Abnormal WHR values were associated with a 28 percent higher likelihood of poor physical performance

Abnormal WHtR values were linked to a 32 percent higher likelihood of poor physical performance

RELATED: 6 Supplements That Can Help You Burn Belly Fat Fast, Doctors Say.

Researchers believe visceral fat can lead to decreased physical function.

One strong theory relates to the distribution of fatty tissue in the stomach, also known as visceral fat.

“A higher WHR and/or WHtR typically indicates a higher amount of abdominal fat, which has been associated with various health risks and decreased physical function. Excess abdominal fat is known to contribute to decreased muscle strength, flexibility, and overall mobility, which can subsequently hinder physical performance,” wrote the authors.

Additionally, when visceral fat encroaches on vital organs, it can “impair cardiovascular function and metabolic health.” This can lead to decreased endurance and aerobic performance.

If you’re struggling to lose stubborn belly fat or have concerns about your health, speak with a doctor who can conduct a thorough assessment and even refer you to a nutritionist.

As the authors concluded, “These measurements serve as easily accessible tools that empower individuals to make informed lifestyle choices, contributing to their overall well-being and the potential for a healthier and longer life.”

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