Studies suggest that emphasizing the lowering phase of movements such as squats, pushups and stair walking can increase strength, improve balance and support cardiovascular health while requiring less oxygen than traditional lifting movements.
By yourNEWS Media Newsroom
The lowering phase of everyday movements may provide greater fitness benefits than many people realize, with research indicating that eccentric exercise can build substantial muscle strength while placing less demand on the cardiovascular system.
Eccentric exercise occurs when a muscle lengthens while under tension. Examples include lowering into a chair, descending stairs, slowly lowering a weight or controlling the downward portion of a pushup.
Unlike concentric contractions, in which muscles shorten while producing force, eccentric movements can generate greater force with lower oxygen consumption and less cardiovascular strain. That combination has drawn increasing interest from researchers studying exercise options for older adults, beginners and people recovering from injuries.
Kazunori Nosaka, director of Exercise and Sports Science at Edith Cowan University in Western Australia, has reported findings showing that eccentric contractions can generate more than 20% greater force than concentric movements while requiring less oxygen and producing lower heart rates.
The efficiency partly stems from the way muscles, tendons and connective tissues handle force during lengthening. Elastic components within the muscle-tendon system can store and release energy, allowing the body to resist a load with less metabolic demand than is required to lift it.
That helps explain why lowering a heavy object typically feels easier than raising it even though the muscles remain under considerable tension.
Muscles generally operate through three types of contraction. Concentric contractions shorten the muscle, isometric contractions maintain tension without changing muscle length and eccentric contractions lengthen the muscle while it resists a force.
Eccentric exercise was historically less understood than other forms of muscle contraction. Lindsey Lepley, associate professor of athletic training at the University of Michigan School of Kinesiology, has noted that researchers once struggled to explain how muscles could continue producing substantial force while being stretched.
One drawback associated with eccentric exercise is delayed onset muscle soreness, commonly known as DOMS. The discomfort often appears one to three days after an unfamiliar workout and can be especially noticeable after movements involving prolonged lowering.
Research, however, suggests that the body adapts quickly.
Nosaka’s work has examined what researchers call the “repeated bout effect,” in which one or two sessions of eccentric exercise substantially reduce soreness and stiffness during subsequent sessions.
The adaptation appears to involve both muscular tissue and the nervous system. As the body becomes familiar with eccentric loading, it learns to distribute force more effectively across muscle fibers and surrounding tissues.
Even relatively low-intensity eccentric exercise can create that protective adaptation, meaning the first unfamiliar session may produce considerably more soreness than later workouts involving similar movements.
Some of the most notable findings have come from studies examining stair walking.
In one study, elderly women who walked downstairs twice per week for 12 weeks experienced greater improvements in several health measures than participants who concentrated on walking upstairs.
The group performing stair descent recorded a 10% reduction in resting heart rate, a 9% decline in systolic blood pressure, a 13% reduction in LDL cholesterol and a 34% increase in lower-body strength.
Descending stairs places substantial eccentric demand on muscles because the legs must repeatedly control the body’s downward movement while absorbing force.
Laura Richardson, clinical associate professor at the University of Michigan School of Kinesiology, has said the approach can provide greater mechanical loading than level walking without requiring the same cardiovascular effort as climbing.
“You don’t have to be super fit to walk down a flight of steps,” Richardson said.
Researchers have also examined short eccentric routines that can be completed at home.
One study used a five-minute program incorporating movements such as chair squats, wall pushups, chair reclines and heel drops. After eight weeks, participants showed improvements in flexibility, muscular strength and mental health.
More than 90% of participants continued exercising afterward, suggesting that the relatively simple program may also encourage long-term adherence.
A beginner can incorporate eccentric exercise by deliberately slowing the lowering portion of familiar movements. A chair squat, for example, can be performed by taking approximately five seconds to lower into the chair before standing normally.
Wall pushups can be modified in the same way by slowly allowing the body to move toward the wall before pushing away. Heel drops performed from a step and controlled lowering during abdominal exercises can also provide eccentric loading without specialized equipment.
Researchers recommend beginning conservatively, often with five to 10 repetitions for one or two sets, and emphasizing slow, controlled movement rather than speed.
Several days of recovery between unfamiliar eccentric workouts may help minimize soreness. Mild discomfort appearing a day or two after exercise is common, while significant soreness lasting longer than about three days can indicate that the intensity or volume should be reduced.
Eccentric movements can also be incorporated into ordinary activities rather than performed exclusively as structured workouts. Slowly sitting into a chair, deliberately controlling a descent down stairs and carefully lowering groceries or other objects can place muscles under eccentric tension.
Those movements may be particularly useful for strengthening the muscles involved in stabilizing the knees and hips and controlling balance.
Eccentric training can also influence the nervous system because controlled lowering requires continuous coordination between muscles and the brain.
The body must constantly adjust force as a muscle lengthens, which can improve movement control, balance, joint stability and the ability to absorb forces that might otherwise contribute to injury.
Research has also documented a “cross-education” effect, in which eccentric exercise performed with one limb increases strength in the corresponding untrained limb.
Scientists believe the effect results largely from changes in the brain and spinal cord rather than direct changes in the untrained muscle. Neural pathways involved in movement can become more efficient even when only one side of the body is actively exercised.
That finding could have implications for rehabilitation when an injured or surgically repaired limb cannot be trained directly.
The growing research on eccentric exercise suggests that greater effort is not always necessary to produce meaningful physical benefits. Controlled lowering movements can provide substantial mechanical loading while demanding less oxygen and cardiovascular work than many traditional exercises.
For older adults and people beginning a fitness program, simple activities such as descending stairs or slowly sitting into a chair may provide an accessible way to strengthen muscles, improve coordination and increase the body’s ability to safely absorb force.
Source: Natural News
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