Heavy Resistance Training Preserves Leg Strength in Older Adults for Up to Four Years

Building and maintaining strong muscles helps with function and contributes to well-being. Muscle function typically declines in older adults, which may lead to reduced mobility and independence and increase the risk of falls. Resistance training, which involves using weight to help with muscle strength, is one such intervention. A recent study published in BMJ Open Sport & Exercise Medicine examined the long-term benefits of heavy resistance training for older adults. 

The study found that one year of heavy resistance training helps older adults maintain isometric leg strength for up to four years. The findings suggest that heavy resistance training may help with long-term muscle function preservation. The current study examined some long-term benefits of heavy resistance training. It was an interim analysis of the LIve Active Successful Ageing (LISA) study, a parallel group randomized controlled trial. 

The trial included 451 older adults who were divided into three groups.As noted in the previous outline for the LISA study protocols, the high-resistance training group used exercise machines for activities like leg and chest presses, low rowing, and leg curls. 

In contrast, the moderate-intensity training group did exercises like squats, push-ups, and seated low rowing. While the heavy resistance training group used exercise machines, the moderate intensity training group used elastic exercise bands and their body weight for resistance. 

Both groups also did abdominal and lower back exercises to help build core strength. The heavy resistance training group worked at a private fitness center three times a week. In contrast, the moderate resistance group did one weekly training session at a hospital and two weekly exercise sessions at home. 

This outline also noted that the control group was expected to continue habitual physical activity levels, less than 1 hour of regular strenuous weekly activity. This current analysis followed up with participants three years after the end of the one-year intervention. 

Researchers conducted tests to examine the visceral fat mass, isometric leg strength of the quadriceps, and maximal isometric quadriceps torque. They also performed brain and thigh MRI scans and tracked daily step counts for participants. These were the same tests that participants had undergone at baseline, post-intervention, and one year after post-intervention. 

Overall, the benefits for the heavy resistance training group were the highest at the 4-year mark.The heavy resistance group maintained its baseline performance for isometric leg strength, while the other groups experienced a decline. However, researchers note that the decrease in isometric leg strength for the moderate-intensity group was insignificant. 

Both resistance training groups did not experience a change in visceral fat content over the four years, while the control group experienced an increase in visceral fat content. All three groups also experienced similar decreases in handgrip strength, lean leg mass, and leg extensor power. 

Researchers believe the benefits of resistance training for leg strength could be due to neural adaptations, even when things like leg lean mass decrease. 

Despite the implications, this research has some limitations. First, since this was an interim analysis of a previous intervention, researchers are limited by any limitations in the LISA study. For example, it was conducted in Denmark, meaning the results cannot necessarily be generalized to other population groups. 

Further, these findings cannot establish causality, and some data relies on participant reporting. Some differences between how interventions were conducted could have made a difference in the results as well. 

Researchers also note that the participants in the study were likely healthier and more active than the average aging population. Not all participants who started the study were present at follow-up either. 

While this study points to the idea that heavy resistance training may benefit older adults most, it doesn’t mean that other forms of resistance training aren’t helpful. It is never too late to begin resistance training as it will only help with functional (everyday tasks) of living. Older adults can experience significant benefits related to overall health when incorporating strength training, like muscle strength and bone density. Strength training can be tailored to age, abilities, and current health status. 

People who are interested in beginning strength training can take steps to do so safely and at a pace that works for them. 

Doctors can recommend exercise regimens and consider things like chronic conditions or other potential risks that a person may have. Working with a personal trainer or physical therapist can also help you safely integrate resistance training into your routine. 

Resistance training can include activities like lifting weights or using resistance bands. People should work to build up strength, starting with lower-weight options rather than heavier ones.