Warning. The following presentation contains information that might contradict what you
have previously heard or believed to be true about how the human body works and contains
material that is not suitable for closed mind and individuals. Enjoy.
We're going to take a look today at the responses that we might see to weight training within
the skeletal muscle. Talking a little bit about muscle damage and recovery that will occur
so that we can get the structural changes that we need in order to be able to see the
gains in strength that occur when we ask the muscle to do more than what the muscle is
able to do. And so we're working out and we work out. We're going to try to gain muscle
and the way we should gain muscle is we have to push ourselves. There's the old adage
of no pain, no gain. And that's pretty true because we have to make the muscle have to
do more than what the muscles is going to be comfortable doing. And so we keep asking
the muscle to do more and the muscle to do more and the muscle to do more. We keep pushing
the muscle. We keep pushing the muscle by adding weight to what we're doing, adding
repetitions while still having a constant weight, doing exercise for longer periods
of time and what we're comfortable of doing when we first started, continually pushing
ourselves to become stronger in our exercises. But as we're doing our exercise, what's happening
inside the muscle that's going to allow us to become stronger. The way in which muscles
are going to respond is based off of the concept of response to overload. Response to overload
is the muscle attempt to maintain strength when the resistance that we're asking them
to move against is greater than what they're capable of moving against. In response to overload,
muscles will undergo a growth signal to produce more muscle or provide the muscle a means
to produce more contractions. The way in which this takes place is through what's referred
to as tension overload or workload overload. Tension overload is where we ask the muscle
to produce a string that is greater than what it's capable of producing at this time. This
occurs through the eccentric phase of the contractions. Sometimes it pertains to the
negatives in gym talk. So when we're in the gym and we're going to do our negatives, what
we're doing is we're creating more weight or asking the muscle to move against more weight
than what we can do on the positive motion. So we're going to say bench press and we're
bench pressing 185 pounds. If I instead of doing 185 pounds, I do 200 pounds. But all
I can do is allow that weight to go from the top of the motion to the bottom of the motion.
That's the negative. That's the eccentric phase. That's where I'm going to have to produce
more tension than what I'm capable of producing. In the excessive workload, what I'm going
to do is I'm going to produce more tension than what I'm normally capable of doing.
I'm going to have to produce more work. We see the excessive workload happen when I go
from being able to do 10 repetitions to trying to do 12 repetitions or going from running
10 minutes to running 11 minutes. The excessive workload occurs when I have some change in
metabolites taking place in the skeletal muscle and around the skeletal muscle. That's going
to lead to what we sometimes refer to as fatigue. With the tension overload, what is happening
is that we end up getting a loss of contraction strength, fatigue, coming in due to damage
within the sarcomaeric, within the contractal part of the skeletal muscle, the part of the
skeletal muscle that's going to actually produce the muscle contraction. If I do this too much,
if I create too much attention overload, I can actually cause the muscle itself to rupture
and become damaged. With the excessive workload, I end up having an inability to recruit the
muscle fiber itself. That means I can't get the muscle to undergo contractions. This is
where we start having fatigue within our contractions. The fatigue that we look at with excessive
workload is not me being tired. It's not my feeling of fatigue after a workout. It's
the inability to move the weight that I'm trying to move after a few repetitions. What
ends up happening is that as we undergo our contractions, we're going to have shortening
of the muscle. And that shortening is going to lead to movement on one end of the muscle
based off of the pattern of motion that we want. And so we start off with our relaxed
muscle. But what happens if I apply a low to, what happens if I pick up a weight and
decide to start doing some weight training? So I load the muscle, I pick up the dumbbell,
I pick up the barbell. The first bit of tension that gets produced within the muscle is coming
from the connective tissue. It's coming from the tendons that are connecting the muscle
to the bone, trying to keep the muscle from moving. And by keeping the muscle from moving,
I'm able to keep the bones from moving. And this allows me to have a static posture. This
puts me into the set position during the lift. I then try to do motion. As I start to do
motion, what I'm going to try to do is I'm going to try to get the moving end of the
muscle to move towards the fixed end of the muscle. I'm going to do this by recruiting
the muscle. As I recruit the muscle, I'm going to start to add tension within the muscle.
I'm going to start to get some muscle shortening taking place. I'm going to keep trying to
recruit the muscle in an attempt to get enough shortening to allow for the movement to take
place in the pattern that I want the movement to take place. And I keep recruiting and I
keep recruiting until I can't get enough strength to overcome the overload. The muscle basically
sends a signal says, I can't do this. Everything within the muscle that I'm trying to recruit
has been recruited. There's nothing left for me to recruit. You can't move anymore. We're
now stuck in the isometric position. Because of the amount of tension being placed on the
muscle, the connective tissue that surrounds the muscle itself and the connection tissue
within the muscle starts to break apart. We overcome the tension limit for the, for that
connective tissue. And we start having sarcomere disruption and we start having muscle fiber
damage. And this will continue until we basically end up getting a stop signal. This is where
I'm fatigued. I'm unable to produce a contraction. This occurs because the sarcomere has been
disrupted and the muscle fibers themselves have been damaged. That damage is what's producing
what's referred to as micro trauma. That micro trauma is going to be within the skeletal
muscle itself as well as within the connective tissue. You can think of this micro trauma
as injury. This injury is coming from damage to the muscle fiber and damage within the
muscle fiber. We get disruption of the sarcomere sarcomere popping. That sarcomere popping
is necessary as it's going to allow us to have recovery following the exercise that's
going to allow for muscle growth to take place. But what it's also going to do is it's also
going to initiate our immune response because we have injury taking place. Immune cells
within the skeletal muscle tissue are going to start to activate an inflammation response.
They're going to become active. They're going to become active to clear out the damaged
tissue so that we're able to start the recovery process. We've overloaded. We've overloaded
in order to get muscle growth. The problem is that we have inflammation. Inflammation
is going to lead to pain. Remember, no pain, no gain. Pain is good when we're looking at
muscle recovery. We're looking at muscle response to exercise. Muscle soreness is important.
Muscle source is what's going to lead to the recovery and the gains that we want within
the muscle. When we look at muscle soreness, we have basically three types of muscle soreness.
We have onset muscle soreness and then injurious muscle soreness. The muscle soreness we want
is the arms and the dombs. We want muscle soreness that will occur acutely, arms, acute onset
muscle soreness. That's muscle soreness that will take place an hour or so after workout
or dombs delayed onset muscle soreness. That's the muscle soreness that's going to take place
24 to 48 hours the next day or two days after the exercise. The arms and the dombs is where
we get sore and it hurts to walk around and move around if we happen to be doing, say,
the leg day where we're stiff and we're sore and we're tired and we don't want to do stuff.
That is the arms and the dombs. That's good soreness. That's soreness that takes place
due to the micro trauma occurring within the exercise. However, we don't want injurious
muscle soreness, the aims, the acute injurious muscle soreness. The acute injurious muscle
soreness is an indication that we have more than just micro trauma taking place. We have
damage to the tendons, damage to the ligaments, damage in the joints of the skeletal part
of the musculoskeletal system, possible muscle tears. Those are the sorenesses that we don't
want. Those sorenesses are very acute. They take place instantaneously. This is not, however,
the burning sensation that you might get during exercise. The burning sensation that
you might get during exercise and the soreness you might experience during an exercise is
part of the arms. The way it is to determine if it's an aims situation or an arms situation
is how sharp is the pain and does the pain limit my ability to do movement with that
muscle. When we're looking at the onset of muscle soreness issues is a cascade of events
stemming from the immune system. The muscle pain that you feel, the muscle burning that
you feel during exercise is not from lactate or what some people prefer to as lactic acid,
but it's from tissue damage triggering the embedded immune system to become active. When
the immune cells become active, they're going to increase immune signals, immune hormones,
such as interleukin 1, interleukin 6, interferon gamma, TNF alpha, and then a whole host of
prostaglandins. While at the same time they're going to block anti-inflammatory IL-10, interleukin
10, as well as growth hormones such as mechanical growth factor from the cells themselves. What
the activation of the inflammation signals and the blocking of the anti-inflammation
signals do is it increases macrophage activity, it increases a protein within the cells known
as NF, Kappa B, and COX proteins. It's going to trigger myoblast proliferation, more myoblasts
becoming active, but it's not going to allow for differentiation of the myoblasts. So what
it's going to do is it's going to trigger muscle cells, the stem cells that would normally
allow for growth to take place, to start the cascade of events to lead to growth, but it
won't allow growth to occur. It reduces internal signals within the cells in terms of responsiveness
to IL-10. What that does is that increases inflammation within the muscle that's been
worked out. So if we think about it, we work out and we talk about getting swole after
a workout. That swoliness is occurring due to inflammation. It's going to cause a change
in blood flow into the tissues around the cells. It's going to cause movement of fluid
from the blood into the interstitial area, this area around the tissues. Because we get
activation of the fibroblast and the myoblast, we're going to get fibrosis taking place.
We're going to get fibres being laid out, but the fibrosis that are being laid out is
going to increase the likelihood of developing scar tissue, not skeletal muscle tissue. We're
going to have very poor muscle protein synthesis taking place because of the inflammation signals,
in particular high amounts of cortisol taking place. All of these lead to the classical
signs and symptoms of muscle soreness, such as the feelings of pain. The altered muscle
functions reduce the ability to produce strength, reduce maximal strength, reduce maximal power,
reduce maximal workload. Aedema in the tissues, fluid collection in the limb, fluid collection
in the muscle, that's going to make the muscle and make the limb look bigger. The fluid collection
with the altered ability for the muscle to work is going to alter my range of motion.
How easy is it for me to move throughout the entire range that I should be moving? Because
of the metabolic stress that's taking place, we're going to have a large amount of oxidative
stress occurring. We're going to have an increase in our signals of oxidative stress. We're
going to have a reduction in our antioxidant capacity. We're going to use up a lot of our
antioxidant vitamins. We're going to need to supplement those antioxidant vitamins.
We're going to have large amounts of muscle damage induced inflammation. We're going to
see increase in white blood cells. We're going to see increase in the granulocytes, in the
gastronophils, in the basal fills, in the macrophages, in the T cells and V cells. We're going to
see a whole host of pro-inflammatory signals, the IL-6, the TNF-alpha, the C-reactive proteins,
which is going to change the way in which blood flow is moving around the body. All
of those factors come into play to trigger inflammation. The more inflammation I have,
the poorer my resolution will be. I need resolution in order to allow the muscle to become functional,
in order to replace damage skeletal muscle with active functional skeletal muscle. We
need to have pain in order to have gains. We need arms and we need doms, but we need
to get over it.