More than anything, IMHO this will spur R&D into androgen receptor development. This will be in the forms of SARMs or other downstream activators for muscle formation.
Astronaut Strength In Space Equal To 80-Year-Olds
Astronaut Strength In Space Equal To 80-Year-Olds
MARCIA DUNN
08/20/10
CAPE CANAVERAL, Fla. — Astronauts can become as weak as 80-year-olds after six months at the International Space Station, according to a new study that raises serious health concerns as NASA contemplates prolonged trips to asteroids and Mars.
Marquette University biologist Robert Fitts, who led the study, stresses that the accelerated space aging is temporary: Astronauts' muscles recover after a few months back on Earth.
But what if a crew needed to make an emergency landing here on the home planet and rush from a burning spacecraft? What if after arriving at Mars, an urgent spacewalk was needed for repairs? Would the Mars men and women even be able to muster the strength for routine work?
"I'd be concerned," Fitts said this week in an interview with The Associated Press.
Astronauts can avoid becoming weaklings, however, with more research and the right equipment for hitting the space gym, Fitts observed. "I really think this is all preventable," he said.
Fitts bases his findings on calf muscle biopsies that his team collected on nine U.S. and Russian space station residents from 2002 to 2005. It's the first muscle study of long-flying astronauts that gets down to the cellular level, with actual biopsies conducted.
Each astronaut spent six months aboard the orbiting lab, and submitted to a biopsy before rocketing away and immediately upon returning to Earth.
The researchers discovered that the astronauts had lost more than 40 percent of the power in the slow-twitch fibers of their calf muscles. Those are the muscles so crucial for balance and posture, and seem to take more of a space-beating than other parts of the body.
Fitts said the muscle decline in the 40-something space station astronauts was equivalent to that of a person twice as old.
It didn't matter how musclebound someone was going into the mission. Fitts said the strongest weightlifting astronauts suffered the greatest muscle atrophy in orbit.
This considerable deterioration of the calf muscles occurred even though the astronauts devoted one to two hours a day to exercise. NASA has long realized the importance of weightless workouts, and the space station is equipped with treadmills, stationary cycles, and resistive-exercise machines for leg squats and calf raises.
NASA expects a new resistive exercise machine flown up last year to improve upon the old one. Tests are planned to see if that bears out. Astronauts complained that using the old model was like lifting a barbell without weights.
As it is now, astronauts returning from six-month space station missions must undergo physical therapy and, because of balance issues, cannot drive for two to four weeks. An expedition to Mars would last a minimum of three years.
Besides better exercise routines and equipment, astronauts also need to eat more, Fitts noted.
Studies on Earth show that subjects confined to bed as a way of simulating weightlessness need to consume an adequate amount of calories to benefit from exercise. And they need to have their meals soon after workouts, he said.
"Every one of the crew members studied on this flight ... they didn't eat enough," Fitts said.
The same thing happened on Russia's old Mir space station; caloric intake did not meet caloric demand, he said. What's more, food needs to be eaten shortly following exercise, in order to build muscle mass. Some astronauts, indeed, return to Earth thinner.
Astronauts' appetites apparently are poor in orbit, in part because of the often taxing workload, Fitts said. During the past few weeks, for example, the space station's six-person crew was preoccupied with a broken ammonia coolant pump that had to be replaced in a series of spacewalks.
"They have a lot of dietitians who say, 'This is the perfect diet.' Well, if you eat it, it's probably the perfect diet," he said with a chuckle.
Gregory Adams, a physiologist at the University of California at Irvine who conducts research for NASA's National Space Biomedical Research Institute, said the calf muscles are particularly vulnerable and difficult to train in weightlessness - in other words, "the worst-case scenario."
"So I am a little bit more cautious in extrapolating that to all the rest of the muscles of the body," Adams said.
And every astronaut is different, he noted. Because of genetics, some individuals seem to experience more muscle atrophy in space no matter how much or how well they exercise.
The NASA-funded work by Fitts and his team has been published online by The Journal of Physiology, and will be included in the September issue.
Fitts RH, Trappe SW, Costill DL, et al. Prolonged Space Flight-Induced Alterations in the Structure and Function of Human Skeletal Muscle Fibres. The Journal of Physiology. Prolonged Space Flight-Induced Alterations in the Structure and Function of Human Skeletal Muscle Fibres — J Physiol
The primary goal of this study was to determine the effects of prolonged space flight (~180 days) on the structure and function of slow and fast fibres in human skeletal muscle. Biopsies were obtained from the gastrocnemius and soleus muscles of nine International Space Station crew members ~ 45 days pre- and on landing day (R+0) post-flight. The main findings were that prolonged weightlessness produced substantial loss of fibre mass, force, and power with the hierarchy of the effects being soleus type I > soleus type II > gastrocnemius type I > gastrocnemius type II. Structurally, the quantitatively most important adaptation was fibre atrophy which averaged 20% in the soleus type I fibres (98 to 79 µm dia). Atrophy was the main contributor to the loss of peak force (P0) which for the soleus type I fibre declined 35% from 0.86 to 0.56 mN. The % decrease in fibre diameter was correlated with the initial pre-flight fibre size (r= 0.87), inversely with the amount of treadmill running (r = 0.68), and was associated with an increase in thin filament density (r = 0.92). The latter correlated with reduced V0 (r = -0.51), and likely contributed to the 21 and 18 % decline in V0 in the soleus and gastrocnemius type I fibres. Peak power was depressed in all fibre types with the greatest loss (~55%) in the soleus. An obvious conclusion is that the exercise countermeasures employed were incapable of providing the high-intensity needed to adequately protect fibre and muscle mass, and that the crew's ability to perform strenuous exercise might be seriously compromised. Our results highlight the need to study new exercise programs on the ISS that employ high resistance and contractions over a wide range of motion to mimic the range occurring in Earth’s 1 g environment.
Astronaut Strength In Space Equal To 80-Year-Olds
Astronaut Strength In Space Equal To 80-Year-Olds
MARCIA DUNN
08/20/10
CAPE CANAVERAL, Fla. — Astronauts can become as weak as 80-year-olds after six months at the International Space Station, according to a new study that raises serious health concerns as NASA contemplates prolonged trips to asteroids and Mars.
Marquette University biologist Robert Fitts, who led the study, stresses that the accelerated space aging is temporary: Astronauts' muscles recover after a few months back on Earth.
But what if a crew needed to make an emergency landing here on the home planet and rush from a burning spacecraft? What if after arriving at Mars, an urgent spacewalk was needed for repairs? Would the Mars men and women even be able to muster the strength for routine work?
"I'd be concerned," Fitts said this week in an interview with The Associated Press.
Astronauts can avoid becoming weaklings, however, with more research and the right equipment for hitting the space gym, Fitts observed. "I really think this is all preventable," he said.
Fitts bases his findings on calf muscle biopsies that his team collected on nine U.S. and Russian space station residents from 2002 to 2005. It's the first muscle study of long-flying astronauts that gets down to the cellular level, with actual biopsies conducted.
Each astronaut spent six months aboard the orbiting lab, and submitted to a biopsy before rocketing away and immediately upon returning to Earth.
The researchers discovered that the astronauts had lost more than 40 percent of the power in the slow-twitch fibers of their calf muscles. Those are the muscles so crucial for balance and posture, and seem to take more of a space-beating than other parts of the body.
Fitts said the muscle decline in the 40-something space station astronauts was equivalent to that of a person twice as old.
It didn't matter how musclebound someone was going into the mission. Fitts said the strongest weightlifting astronauts suffered the greatest muscle atrophy in orbit.
This considerable deterioration of the calf muscles occurred even though the astronauts devoted one to two hours a day to exercise. NASA has long realized the importance of weightless workouts, and the space station is equipped with treadmills, stationary cycles, and resistive-exercise machines for leg squats and calf raises.
NASA expects a new resistive exercise machine flown up last year to improve upon the old one. Tests are planned to see if that bears out. Astronauts complained that using the old model was like lifting a barbell without weights.
As it is now, astronauts returning from six-month space station missions must undergo physical therapy and, because of balance issues, cannot drive for two to four weeks. An expedition to Mars would last a minimum of three years.
Besides better exercise routines and equipment, astronauts also need to eat more, Fitts noted.
Studies on Earth show that subjects confined to bed as a way of simulating weightlessness need to consume an adequate amount of calories to benefit from exercise. And they need to have their meals soon after workouts, he said.
"Every one of the crew members studied on this flight ... they didn't eat enough," Fitts said.
The same thing happened on Russia's old Mir space station; caloric intake did not meet caloric demand, he said. What's more, food needs to be eaten shortly following exercise, in order to build muscle mass. Some astronauts, indeed, return to Earth thinner.
Astronauts' appetites apparently are poor in orbit, in part because of the often taxing workload, Fitts said. During the past few weeks, for example, the space station's six-person crew was preoccupied with a broken ammonia coolant pump that had to be replaced in a series of spacewalks.
"They have a lot of dietitians who say, 'This is the perfect diet.' Well, if you eat it, it's probably the perfect diet," he said with a chuckle.
Gregory Adams, a physiologist at the University of California at Irvine who conducts research for NASA's National Space Biomedical Research Institute, said the calf muscles are particularly vulnerable and difficult to train in weightlessness - in other words, "the worst-case scenario."
"So I am a little bit more cautious in extrapolating that to all the rest of the muscles of the body," Adams said.
And every astronaut is different, he noted. Because of genetics, some individuals seem to experience more muscle atrophy in space no matter how much or how well they exercise.
The NASA-funded work by Fitts and his team has been published online by The Journal of Physiology, and will be included in the September issue.
Fitts RH, Trappe SW, Costill DL, et al. Prolonged Space Flight-Induced Alterations in the Structure and Function of Human Skeletal Muscle Fibres. The Journal of Physiology. Prolonged Space Flight-Induced Alterations in the Structure and Function of Human Skeletal Muscle Fibres — J Physiol
The primary goal of this study was to determine the effects of prolonged space flight (~180 days) on the structure and function of slow and fast fibres in human skeletal muscle. Biopsies were obtained from the gastrocnemius and soleus muscles of nine International Space Station crew members ~ 45 days pre- and on landing day (R+0) post-flight. The main findings were that prolonged weightlessness produced substantial loss of fibre mass, force, and power with the hierarchy of the effects being soleus type I > soleus type II > gastrocnemius type I > gastrocnemius type II. Structurally, the quantitatively most important adaptation was fibre atrophy which averaged 20% in the soleus type I fibres (98 to 79 µm dia). Atrophy was the main contributor to the loss of peak force (P0) which for the soleus type I fibre declined 35% from 0.86 to 0.56 mN. The % decrease in fibre diameter was correlated with the initial pre-flight fibre size (r= 0.87), inversely with the amount of treadmill running (r = 0.68), and was associated with an increase in thin filament density (r = 0.92). The latter correlated with reduced V0 (r = -0.51), and likely contributed to the 21 and 18 % decline in V0 in the soleus and gastrocnemius type I fibres. Peak power was depressed in all fibre types with the greatest loss (~55%) in the soleus. An obvious conclusion is that the exercise countermeasures employed were incapable of providing the high-intensity needed to adequately protect fibre and muscle mass, and that the crew's ability to perform strenuous exercise might be seriously compromised. Our results highlight the need to study new exercise programs on the ISS that employ high resistance and contractions over a wide range of motion to mimic the range occurring in Earth’s 1 g environment.
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