- Retirement-age people who followed a strength-training program for 12 months had significantly stronger leg muscles three years after completing the program than those who did more moderate or no strengthening exercises. , according to the study.
- The strength training group went to a commercial gym three times a week for a year and repeatedly lifted what was considered a heavy load: 70 to 85 percent of the maximum weight a person can physically lift at one time.
- Although the The supervised program lasted only a year, with scientists following up three years later. Individuals in the “heavy” weightlifting cohort were the only participants who maintained, on average, the leg strength they had before starting the training program.
In particular, leg strength is an essential indicator of health and mobility in older people. These findings add to a growing body of evidence suggesting that weightlifting can help older adults avoid frailty and stay healthy as they age.
“Leg strength is really important,” Mads Bloch-Ibenfeldt, a medical researcher at the University of Copenhagen who co-authored the study, said in a telephone interview Wednesday. “We use our legs in many everyday tasks, such as getting up and down from a chair. So it’s important for reducing the risk of falls and for many everyday tasks we do.
Bodybuilding training
As part of the study, scientists at a university hospital in Copenhagen divided 451 people of retirement age into three randomized groups, each assigned to follow a different year-long exercise program.
- The “heavy” bodybuilding group visited a commercial gym three times a week for a supervised full-body strength training program.
- Participants determined the maximum weight they could lift at one time using typical weight machines found in gyms. Then, they calculated 70 to 85 percent of their one-rep max and used that weight in their training. So if the most they could lift at one time was 100 pounds, they used weights of 70 to 85 pounds in their training.
- They trained 3 times a week, performing three sets of each exercise. Each set consisted of 6 to 12 repetitions.
- The routine included a mix of nine upper and lower body exercises: leg press, knee extension, leg flexion, ankle plantar selection, hip abduction, low rowing, chest press, abdominal crunches and exercises for lower back.
- Although the scientists described the diet as “heavy” strength training compared to two other groups in the study, the strength training program was similar to most standard strength training workouts.
Training with heavy weights or moderate resistance
The second group completed a year-long moderate-intensity training program using body weight and resistance bands three times a week. The resistance bands were less difficult than the weights in the heavy group — about 50 to 60 percent of the maximum weight a person can lift at one time.
The third cohort was a control group that did less than one hour of intense exercise per week.
For four years, The scientists looked at participants’ physical strength, including leg strength, grip strength, and lean leg mass. The researchers measured participants’ strength at the start of the 12-month supervised training program and then again after it finished. They followed another year after its end, and three years after its end.
After three years, the researchers noted that a small minority of exercise participants continued the same program of their own accord, but the benefits of the intensive training were maintained.
“We found that if you did a year of resistance training with heavy weights, you were able to maintain the strength in your legs that you had at the start of the study,” Bloch-Ibenfeldt said.
The other groups were found to have lost strength from their baselines. Four years after the start of the study, leg strength performance declined on average among members of the moderate-intensity training cohort and the non-exercising control group – although more significantly among the latter. Those who followed the moderate program initially benefited from an increase in their leg strength at the end of the one-year program, but these benefits did not last: after four years, their strength was below what it was. she was at the start.
The scientists observed that all three groups, including those lifting the heaviest weights, had decreased grip strength and lean mass in their legs after four years.
But the fact that the heavy lifting group retained their core leg strength while losing lean mass in their legs was remarkable, the authors observed, highlighting some of the potential neuromuscular benefits of weight training beyond muscle development.
“Neural adaptations influence the response to resistance training,” they wrote. “In conclusion, we have shown that in a group of healthy older adults near retirement age, one year of intense resistance training can induce lasting beneficial effects by preserving muscle function.”
At the end of the study, the average age of the remaining 369 participants was 71 years old and included 61 percent women.
The researchers noted that the participants were likely healthier and more active than the average aging population, given that they averaged nearly 10,000 daily steps as a sample group. They noted that this group was not necessarily a representative sample of the broader population.
Additionally, the year-long training program was supervised, with participants’ technique and load monitored and adjusted, meaning it might be difficult for participants to replicate on their own.
Why leg strength is important as we age
According to a study from the National Institute on Aging, age-related loss of muscle mass and strength – known as sarcopenia – significantly contributes to limited mobility in older age, which can in turn threaten a person’s physical independence. Seniors with limited mobility may have difficulty walking, climbing stairs, and getting out of chairs.
Leg strength in particular – which is crucial for balance and mobility – is associated with better health outcomes for older adults. Research suggests that people over 50 with lower power levels in their legs are more likely to also suffer from chronic health conditions, although more research is needed.
Federal guidelines suggest adults over age 65 should engage in muscle-strengthening activities weekly, along with regular aerobic activity and exercises to improve balance.
“In addition to aerobic activity, older adults should do activities to strengthen their muscles at least 2 days a week. Do muscle-strengthening activities to the point that it is difficult to do another repetition without assistance,” the Centers for Disease Control guidelines state. According to the CDC, this could include lifting weights, working with resistance bands, or doing activities involving body weight like sit-ups.