training and preferential muscle recruitment?

[TPT]

can we preferentially recruit different muscles by training? well, this study by kulig et al. (2001) suggested that biceps brachii is preferentially recruited with fast eccentric muscle contractions. this possibly is based on biceps being comprised of predominately fast twitch muscle fibers.

the implications for bodybuilders are great, it that, bodybuilders may "target" specific muscles based on their muscle fiber types. why do you guys think? private message me for the full text because i can't seem to attach a damn pdf file.

http://www.acsm-msse.org/pt/re/msse/abstract.00005768-200102000-00004.htm;jsessionid=KCXBsdp1JZvwQGxRNHMDl10hwYgFJ fVGy2xbMh6yb1YLHjYNdp0h!454098877!181195628!8091!-1

The effects of eccentric velocity on activation of elbow flexors: evaluation by magnetic resonance imaging.

CLINICAL SCIENCES
Medicine & Science in Sports & Exercise. 33(2):196-200, February 2001.
KULIG, KORNELIA; POWERS, CHRISTOPHER M.; SHELLOCK, FRANK G.; TERK, MICHAEL

Abstract:
KULIG, K., C. M. POWERS, F. G. SHELLOCK, and M. TERK. The effects of eccentric velocity on activation of elbow flexors: evaluation by magnetic resonance imaging. Med. Sci. Sports Exerc., Vol. 33, No. 2, 2001, pp. 196-200.
Purpose: To compare magnetic resonance imaging (MRI) signal intensity changes in the primary elbow flexors during two isotonic exercise protocols varying in eccentric velocity and the ratio of eccentric to concentric activity.
Methods: Twelve men performed two exercise protocols. The right and left arms were randomly assigned to one of two protocols that had the same workload (60% 1RM) and same total time of exercise (144 s) but differed in the velocity and ratio of eccentric to concentric activity (1:1 and 5:1 for the fast and slow protocols, respectively). MRI signal intensity changes were quantified pre- and post-exercises using an inversion recovery sequence with a 1.5T MRI system (TR = 2500 ms, TE = 90 ms, TI = 140 ms). Percent change in MRI signal intensity, rate of perceived exertion (RPE), and delayed onset muscle soreness (DOMS) were recorded and analyzed.
Results: The biceps brachii was found to be preferentially recruited during the fast protocol compared with the brachialis, whereas the brachialis was found to be preferentially recruited during the slow protocol (P < 0.05). The fast exercise protocol was perceived as being more strenuous (RPE = 8.3 +/- 2.1) than the slow (RPE = 5.4 +/- 1.5, P < 0.05) and produced DOMS in 58% of the tested subjects. Conclusions: These results suggest that agonists respond to various loading conditions nonhomogeneously. These findings may have implications with respect to exercise prescriptions for specific muscles.

[Dr Pangloss]

hmmm. how are they doing a "fast eccentric" muslce contractions? Since this is the negative, what do they do? Just amp up the load on the negative?

[TPT]

hmmm. how are they doing a "fast eccentric" muslce contractions? Since this is the negative, what do they do? Just amp up the load on the negative?


their were two protocols- fast or slow. the loads were 60 % of the subject's 1 rep max. fast protocol eccentric component was 2 sec 3 sets of 12 reps. the slow protocol eccentric component 10 sec in duration 3 sets of 4 reps.


the results suggested that fast twitch muscles might be recruited more when we allow our eccentric contractions to be brief. this is a bit counterintuitive since most of us train with slower eccentric muscle contractions.

[Dr Pangloss]

their were two protocols- fast or slow. the loads were 60 % of the subject's 1 rep max. fast protocol eccentric component was 2 sec 3 sets of 12 reps. the slow protocol eccentric component 10 sec in duration 3 sets of 4 reps.


the results suggested that fast twitch muscles might be recruited more when we allow our eccentric contractions to be brief. this is a bit counterintuitive since most of us train with slower eccentric muscle contractions.



boy that seems counterintuitive. But hey, i'm likely to believe it. So what do you make of all this HIT training where they slow the negative down to a crawl? Mentzer used to love to do that.

[TPT]

boy that seems counterintuitive. But hey, i'm likely to believe it. So what do you make of all this HIT training where they slow the negati"inve down to a crawl? Mentzer used to love to do that.


scientific data indicate that eccentric contractions are particularly "injurious" or "damaging" to skeletal muscles. of course bodybuiders would prefer to best damage muscles per se in hopes of muscle hypertrophy. in regards to the longer durations of time under tension of eccentric contractions used in hit or heavy duty, all muscles whether fast or slow twitch fibers would be greatly affected if high loads are used. mentzer got it right, in that, the negatives should be emphasized for muscle damage and hypertrophy. the studies on muscle damage and injury demostrate this. i suspect that "failure" or "going beyond failure" during eccentric contractions has incredible effects to muscle damage (and hypertrophy).

although, the article by kulig et al. (2001) suggests slow twitch muscles would be preferentially recruited. i.e., muscles used more for stabilizing the joints of the body might be stressed more. we might have greater effects on muscle damage (and hypertrophy) if we vary the rep speed during negatives.

[Frosty]

Varying eccentric speed makes sense, since many muscles have more variance in fiber makeup than others. For example quads vary a lot while the gastroc and hamstring group almost always tend to be more fast twitch, and of course some like the soleus and erector spinae tend to be more slow twitch. So when there are multiple muscles that can act during the lift it can really change things, like with the curl since you have both the biceps brachii and brachialis performing elbow flexion.

Or you could even do it something like this. Start out with 5x6 on a lift, using 2-4 minute rest intervals depending on the lift being used. Fast concentric, quick but controlled eccentric, and you tend to recruit the fast twitch fibers better. Then finish off afterwards with, for example, 4x12 on the lift, with incomplete rest intervals and slower eccentrics.

With this example, in the first portion of the training you'd preferentially recruit fast twitch fibers, working to tap into higher threshold motor units and neuromuscular "learning" of the lift...working both muscle and nervous system. This increases strength and hypertrophy.

In the supplemental portion, you'd stress energy systems and slower twitch muscle fibers to a greater degree. You'd end up exhausting a lot more of the muscle fibers in the target muscles since muscles aren't just all fast or all slow twitch. You'd also get some beneficial metabolic adaptations like increased mitochodrial density, increased capillary density (improves insulin sensitivity), increased nutrient storage and sarcoplasmic hypertrophy, and as well as improving conditioning and strength-endurance so that you can use heavier weights in a higher rep range to further increase hypertrophy through the idea (hypertrophy)=(time under tension)*(load).

[TPT]

[quote=Frosty;244327]Varying eccentric speed makes sense, since many muscles have more variance in fiber makeup than others. For example quads vary a lot while the gastroc and hamstring group almost always tend to be more fast twitch, and of course some like the soleus and erector spinae tend to be more slow twitch. So when there are multiple muscles that can act during the lift it can really change things, like with the curl since you have both the biceps brachii and brachialis performing elbow flexion.

accurate.

Or you could even do it something like this. Start out with 5x6 on a lift, using 2-4 minute rest intervals depending on the lift being used. Fast concentric, quick but controlled eccentric, and you tend to recruit the fast twitch fibers better. Then finish off afterwards with, for example, 4x12 on the lift, with incomplete rest intervals and slower eccentrics.

nice variance and application. most of us are inherently limited by the concentric contractions and load that we never set the occasion for eccentric contractions and progressive loads. essentially, we can't lift the damn weight anymore to take advantage of the eccentric effects.

this is when spotters or machines can have great utility. e.g., when performing a variation of the aforementioned protocol, spot yourself during unilateral curls as you quickly go into failure during the concentric contractions. you will have fatigued the biceps much earlier concentriclly than eccentrically. now you may fatigue the biceps eccentrically as it goes towards failure.

[Frosty]

Good point on the eccentrics. Some lifts are excellent at allowing these, such as any variation of pullups, and many rows allow for a cheat concentric with a strict eccentric, or using weights greater than you can use for concentrics. Unilateral movements are cool for this like you mentioned. But honestly squatting is rough enough is anyone really going to do forced eccentrics? lol. I could see on a leg press lifting with both and lowering with one, but yikes.

ThePhysicalTherapist, one other interesting topic is accommodating resistance using bands and chains. They work excellent for presses, tricep work, squats, deads, and almost any leg/hip work. For things like biceps and pectoralis I've rigged up some cool methods with bands when training at home that would have the bands offer resistance in the portion of the lift when gravity isn't offering much tension on the target muscle. For example in a preacher curl have a band come into tension near the top of the lift, maybe tied to a bench or DB out so it's at a 45 deg angle to the floor. Kinda cool but pretty impractical in most gyms.

But more to the subject at hand, I think the body can handle training two different ways within a workout, so long as they're separate. If you say mixed it in, and did a set of 5 reps and then did a set of 12, and rested 4 minutes and repeated, I think you will not recruit the higher threshold motor units as well in the later sets of 5, and I don't think you'll target the other fibers as well with the sets of 12 because you'll be weaker from the set of 5 you did before, plus you wouldn't take advantage of the muscular and metabolic adaptations you get from incomplete rest intervals. In mixing them together to hopefully train more aspects of the muscle better, i think you'd end up not training either aspect very well. Or perhaps depending on the split and how you train, it could be set up more like Westside does where you may train one aspect of a muscle group on one day, and another aspect on a different day. They're known for the heavy max effort days say on Monday and then the dynamic effort (power) days 3 days later. Or the more hypertrophy oriented version of say 3x3 Monday and 5x10 on Thursday just for example.

Or another effective method, and in my opinion probably the best, would be twice a day workouts. Do 5x5 earlier in the day with proper rest and cadence to recruit the right fibers, then 4-6 hours later go in and do, say, 5x12 on the same group (maybe different angle if hypertrophy is the main goal), with the appropriate cadence and rest intervals. You'd be stronger for the 5x12 using this method vs. doing it in one workout since your nervous system will be fresher. This means greater loading, which would result in greater hypertrophy.

[TPT]

Good point on the eccentrics. Some lifts are excellent at allowing these, such as any variation of pullups, and many rows allow for a cheat concentric with a strict eccentric, or using weights greater than you can use for concentrics. Unilateral movements are cool for this like you mentioned. But honestly squatting is rough enough is anyone really going to do forced eccentrics? lol. I could see on a leg press lifting with both and lowering with one, but yikes.

ThePhysicalTherapist, one other interesting topic is accommodating resistance using bands and chains. They work excellent for presses, tricep work, squats, deads, and almost any leg/hip work. For things like biceps and pectoralis I've rigged up some cool methods with bands when training at home that would have the bands offer resistance in the portion of the lift when gravity isn't offering much tension on the target muscle. For example in a preacher curl have a band come into tension near the top of the lift, maybe tied to a bench or DB out so it's at a 45 deg angle to the floor. Kinda cool but pretty impractical in most gyms.

But more to the subject at hand, I think the body can handle training two different ways within a workout, so long as they're separate. If you say mixed it in, and did a set of 5 reps and then did a set of 12, and rested 4 minutes and repeated, I think you will not recruit the higher threshold motor units as well in the later sets of 5, and I don't think you'll target the other fibers as well with the sets of 12 because you'll be weaker from the set of 5 you did before, plus you wouldn't take advantage of the muscular and metabolic adaptations you get from incomplete rest intervals. In mixing them together to hopefully train more aspects of the muscle better, i think you'd end up not training either aspect very well. Or perhaps depending on the split and how you train, it could be set up more like Westside does where you may train one aspect of a muscle group on one day, and another aspect on a different day. They're known for the heavy max effort days say on Monday and then the dynamic effort (power) days 3 days later. Or the more hypertrophy oriented version of say 3x3 Monday and 5x10 on Thursday just for example.

Or another effective method, and in my opinion probably the best, would be twice a day workouts. Do 5x5 earlier in the day with proper rest and cadence to recruit the right fibers, then 4-6 hours later go in and do, say, 5x12 on the same group (maybe different angle if hypertrophy is the main goal), with the appropriate cadence and rest intervals. You'd be stronger for the 5x12 using this method vs. doing it in one workout since your nervous system will be fresher. This means greater loading, which would result in greater hypertrophy.



interesting spilts and reasoning. i see you do love volume. lol. well i can chat about training with you forever.

[TPT]

well here is another study by wakeling et al. (2006) suggesting preferential muscle recruitment of the gastroc and soleus. the following are the abstract and link to the full text.

This study investigates the motor unit recruitment patterns between and within muscles of the triceps surae during cycling on a stationary ergometer at a range of pedal speeds and resistances. Muscle activity was measured from the soleus (SOL), medial gastrocnemius (MG) and lateral gastrocnemius (LG) using surface electromyography (EMG) and quantified using wavelet and principal component analysis. Muscle fascicle strain rates were quantified using ultrasonography, and the muscle–tendon unit lengths were calculated from the segmental kinematics. The EMG intensities showed that the body uses the SOL relatively more for the higher-force, lower-velocity contractions than the MG and LG. The EMG spectra showed a shift to higher frequencies at faster muscle fascicle strain rates for MG: these shifts were independent of the level of muscle activity, the locomotor load and the muscle fascicle strain. These results indicated that a selective recruitment of the faster motor units occurred within the MG muscle in response to the increasing muscle fascicle strain rates. This preferential recruitment of the faster fibres for the faster tasks indicates that in some circumstances motor unit recruitment during locomotion can match the contractile properties of the muscle fibres to the mechanical demands of the contraction.
Keywords: muscle, recruitment, fibre-type

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1664648


Now this is not a typical training article but, its application to bodybuiding is apparent. cyclists were subjects and measures including emg activation of the soleus, medial and lateral gastrocs were taken during a cycling activity. soleous was recruited more during slower contractions. this was likely because of the predominant type 1 slow muscle type and mechanical variables of being a mono articular muscle. while the gastrocs were preferentially recruited with faster contractions.

some applications for bodybuilders would include changing rep speed to possibly recruit soleus versus gastroc along with flexing or extending the knees while plantarflexing.

[Frosty]

some applications for bodybuilders would include changing rep speed to possibly recruit soleus versus gastroc along with flexing or extending the knees while plantarflexing.

Okay, so let me see if I follow wrt to calf muscle recruitment.

With the knee flexed, since the gastroc is bi-articulate, it would take it significantly out of the movement of plantar flexsion due to the short length of the muscle fibers. So in a seated calf machine, you can potentially recruit the soleus more because the gastroc contraction is fairly inhibited. Is this correct?

So assuming I got that right, then with the seated calf machine, you want slooooower reps? No bouncing bullshit like you see people do? Slow and controlled to preferentially recruit the soleus, and I would also guess due to the general slow twitch fiber type of the soleus that you would want a great deal more time under tension in order to produce a hypertrophy response. So I'm thinking like 40-60 seconds (or more) done with slow reps of full ROM. Would this be correct?

Now to the gastroc. I would assume through an extended knee position to allow a stretch in the bi-articulate gastroc you could allow for better recruitment for plantarflexion since you would stretch the muscle across both the knee and ankle joint. Let's say for example you use a leg press machine with a high seatback position to get a good stretch, then lock the knees.

This is where I'm not as certain about recruitment. Should you then, to preferentially recruit the gastroc and use the soleus less, use fast concentrics? What about slow eccentrics? Would the soleus take over for a slow eccentric? What about pauses in the plantarflexed position? How would this influence gastroc/soleus recruitment? How about holding the stretch in the dorsiflexed position? What would this do for gastroc/soleus recruitment?

[Frosty]

ThePhysicalTherapist, I've been doing some interesting research on nutrients which has led me to some interesting topics, such as the increased requirements for vitamin D, DHA, magnesium, and taurine in fast twitch dominant people, or people doing training that is working the fast twitch fibers hard. Interesting stuff.

[TPT]

Okay, so let me see if I follow wrt to calf muscle recruitment.[/quote][quote=Frosty;270309]

frosty, i know you're interested in all things concerned with growing calves. lol.

With the knee flexed, since the gastroc is bi-articulate, it would take it significantly out of the movement of plantar flexsion due to the short length of the muscle fibers. So in a seated calf machine, you can potentially recruit the soleus more because the gastroc contraction is fairly inhibited. Is this correct?

Correct. since gastroc crosses the knee and is a secondary knee extensor we would need at least 90 degress of knee flexion to put gastroc on slack. thus, stress soleus activation. perfect for the seated calf machine.

So assuming I got that right, then with the seated calf machine, you want slooooower reps? No bouncing bullshit like you see people do? Slow and controlled to preferentially recruit the soleus, and I would also guess due to the general slow twitch fiber type of the soleus that you would want a great deal more time under tension in order to produce a hypertrophy response. So I'm thinking like 40-60 seconds (or more) done with slow reps of full ROM. Would this be correct?

correct. 40-60 seconds under tension seems extreme but, i'll leave that for you to try out. keep in mind that your concentric contractions will fail way before your eccentric contraction. so you'll be able to manage this problem with unilaterals.

Now to the gastroc. I would assume through an extended knee position to allow a stretch in the bi-articulate gastroc you could allow for better recruitment for plantarflexion since you would stretch the muscle across both the knee and ankle joint. Let's say for example you use a leg press machine with a high seatback position to get a good stretch, then lock the knees.

correct. just be carefull with large loads since your knees are in full extension. if it doesn't feel safe, flex the knees 5-10 degrees.

This is where I'm not as certain about recruitment. Should you then, to preferentially recruit the gastroc and use the soleus less, use fast concentrics?

Yes.

What about slow eccentrics?

though fast velocity contractions might be preferred for fast twitch muslces vary the velocity. use slow velociy even for gastroc since it is incredibly aversive and we usually avoid it. with respect to evolution, we hardly ever use gastroc with extended time under tension either for concentric ane eccentric contractions. that itself might give us hints on providing novel stimuli for hypertrophy. i.e., slow contractions.

Would the soleus take over for a slow eccentric?

i doupt it. especially, if you extend the knee. if your hamstrings and glutes are not too tight you can try the calve machines where you flex your spine and hips as if you're bending over. hamstrings are biarticulates that cross the knees/hips and glute max crosses the hip. they both are extensors that will add to the extensor and plantarflexion moment. esentially, you migh lift more weight.

also, you may try to sequence your exercises to preferentially stress soleus or gastroc. e.g., seated calves prior to donkey calves to prefatigue soleus and further stress soleus during your donkey calf raises.

What about pauses in the plantarflexed position?

definately since end range plantarflexion has no natural locking mechanism such as the screw home effect of the knee and other joints. meaning you will still have large amounts of tension forces at end range. so you can't rest.
How would this influence gastroc/soleus recruitment?

negligible differences.

How about holding the stretch in the dorsiflexed position?

do not hold dorsiflexion at end range since most of the tension will be nonmuscular. you would just be resting at end range stretch.

What would this do for gastroc/soleus recruitment?

negligible differences as well.

[Frosty]

Awesome info! Thank you!

About the order of exercises. My first instinct was to do donkey calf raises first to make sure I can tap into the faster twitch fibers, and THEN go hit up the seated calf raise to hit up the slower twitch soleus. With the order reversed, you might work the soleus harder, but wouldn't you possibly compromise recruitment of the fast twitch fibers in the gastroc? Or is the gastroc inhibited enough in the seated calf raise assuming you have a lot of knee flexion during the lift? Meaning the gastroc isn't hardly doing anything and it wouldn't be pre-fatigued hardly at all for when you go to the donkey calf raise.

[TPT]

ThePhysicalTherapist, I've been doing some interesting research on nutrients which has led me to some interesting topics, such as the increased requirements for vitamin D, DHA, magnesium, and taurine in fast twitch dominant people, or people doing training that is working the fast twitch fibers hard. Interesting stuff.


please elaborate. is there a thread on this?

[TPT]

Awesome info! Thank you!

About the order of exercises. My first instinct was to do donkey calf raises first to make sure I can tap into the faster twitch fibers, and THEN go hit up the seated calf raise to hit up the slower twitch soleus. With the order reversed, you might work the soleus harder, but wouldn't you possibly compromise recruitment of the fast twitch fibers in the gastroc? Or is the gastroc inhibited enough in the seated calf raise assuming you have a lot of knee flexion during the lift? Meaning the gastroc isn't hardly doing anything and it wouldn't be pre-fatigued hardly at all for when you go to the donkey calf raise.


yes gastroc would not be stressed if your knees are at 90 degrees. don't worry. i think most of us ignore soleus training so that is partly why i prefer seated calve raises first. plus it is deep to the gastroc and easier to "isolate" in training than gastroc alone.

also, after your gastros-soleus exercises try a close kinetic chain exercise such as a partial squat or leg press. you'll notice that as you squat and descend towards the floor, the hips and knees flex, and your ankles dorsiflex. your soleus is mechanically built to control the anterior translation of the tibia. essentially, you'll be performing an eccentric contraction of the gastroc-soleus. nice way to end your calve training.

[Frosty]

also, after your gastros-soleus exercises try a close kinetic chain exercise such as a partial squat or leg press. you'll notice that as you squat and descend towards the floor, the hips and knees flex, and your ankles dorsiflex. your soleus is mechanically built to control the anterior translation of the tibia. essentially, you'll be performing an eccentric contraction of the gastroc-soleus. nice way to end your calve training.


Cool. What place do you feel ham curls would have in a calve routine (with dorsiflexion to keep the gastroc in the move)? And how about the glute-hamstroc raise? (love these)

[Frosty]

please elaborate. is there a thread on this?


I haven't started a thread on this yet. I've been doing my own research on this topic and trying to put it all together for something more coherent.

I originally got interested in this topic from some tiny little sentences from Poliquin. He stated about athletes involved in high velocity throws depleting taurine and magnesium, and their performance in the gym increases when taurine and Mg levels are restored. He also very quickly mentioned that fast twitch guys need more DHA which I'm trying to research more. Vitamin D is something I found during my own research. There is some out there with athletes that is a bit limited and I'm trying to see if I can find more direct evidence, since most of the research is on elderly. My guess is that it would be involved in calcium and magnesium utilization of the fast twitch fibers, and DHA being involved on the neurological end.

Here's a quick thing on taurine that I happened to have bookmarked:

http://jp.physoc.org/content/538/1/185.abstract

"This study shows that taurine is a modulator of contractile function in mammalian skeletal muscle. Taurine may increase the size of depolarisation-induced force responses by augmenting SR Ca2+ accumulation and release."

[Frosty]

Here's another for you on taurine:

http://www.acsm-msse.org/pt/re/msse/abstract.00005768-200205000-00011.htm;jsessionid=KhLD1LbjtLJz9B5QG089QZvvFfSb5 SFwJL0KLBWsxc2J6d7nx23R!-1775402713!181195628!8091!-1

"Conclusion: Taurine concentration was decreased in all skeletal muscles after exercise, regardless of the duration. Moreover, this decrease was specific to fast-twitch dominant fibers. However, under these conditions, the plasma taurine concentration remained unchanged."

[Frosty]

ThePhysicalTherapist,

I'm getting ready to head off to work but one thing interesting with magnesium is that magnesium depletion leads to reductions in Ca and K, independent of their intake. I can imagine this having effects on muscle contraction, even not considering how Mg itself is involved in muscle contraction. Vitamin D would be involved in both Mg and Ca absorption and metabolism, which I'm still not sure if this is why vitamin D plays a role in maintaining the size and strength of type II fibers in the elderly. A bit less known vitamin is vitamin K2 (MK4 or MK7), and I'm trying to see what I can dig up on this vitamin since it plays a significant role in calcium metabolism and works with vitamin D. However research on this vitamin is lacking, and most of it seems to be on the plant form K1, which is not the same as the animal form K2.

[fury-]

In regards to Magnesium, Kelly Baggett recommends to take about 300mg of magnesium before bed to help recovery... if that means ne thing to u. He is heavy into developing strength and speed and cns recovery

[Frosty]

In regards to Magnesium, Kelly Baggett recommends to take about 300mg of magnesium before bed to help recovery... if that means ne thing to u. He is heavy into developing strength and speed and cns recovery

Magnesium before bed is good, but I think I have a better solution.

This is in addition to Mg before bed. Hard training guys just need more of it, plus Mg can help with sleep quality.

In the post-workout shake with high GI carbs, you take in a good form of magnesium, preferably mixed forms. 400mg or more if you tolerate it. The insulin will shuttle the magnesium into muscle tissue where you want it. Insulin is actually pretty important for having good intracellular magnesium stores, which is in turn important for handling insulin/glucose and other things. You want it in the cells, not outside, which is why insulin is very important to get it in the cells. Also the Mg will help to calm down the CNS after heavy lifting.

[TPT]

I haven't started a thread on this yet. I've been doing my own research on this topic and trying to put it all together for something more coherent.

I originally got interested in this topic from some tiny little sentences from Poliquin. He stated about athletes involved in high velocity throws depleting taurine and magnesium, and their performance in the gym increases when taurine and Mg levels are restored. He also very quickly mentioned that fast twitch guys need more DHA which I'm trying to research more. Vitamin D is something I found during my own research. There is some out there with athletes that is a bit limited and I'm trying to see if I can find more direct evidence, since most of the research is on elderly. My guess is that it would be involved in calcium and magnesium utilization of the fast twitch fibers, and DHA being involved on the neurological end.

Here's a quick thing on taurine that I happened to have bookmarked:

http://jp.physoc.org/content/538/1/185.abstract

"This study shows that taurine is a modulator of contractile function in mammalian skeletal muscle. Taurine may increase the size of depolarisation-induced force responses by augmenting SR Ca2+ accumulation and release."


frosty,

interesting. i will ponder on your descriptions and follow up on these possible deficiencies and their effects on fast twitch musculature.

[TPT]

ThePhysicalTherapist,

I'm getting ready to head off to work but one thing interesting with magnesium is that magnesium depletion leads to reductions in Ca and K, independent of their intake. I can imagine this having effects on muscle contraction, even not considering how Mg itself is involved in muscle contraction. Vitamin D would be involved in both Mg and Ca absorption and metabolism, which I'm still not sure if this is why vitamin D plays a role in maintaining the size and strength of type II fibers in the elderly. A bit less known vitamin is vitamin K2 (MK4 or MK7), and I'm trying to see what I can dig up on this vitamin since it plays a significant role in calcium metabolism and works with vitamin D. However research on this vitamin is lacking, and most of it seems to be on the plant form K1, which is not the same as the animal form K2.


yes. ca, k, and mg are well understood. not sure of vit d as well.

[TPT]

Cool. What place do you feel ham curls would have in a calve routine (with dorsiflexion to keep the gastroc in the move)? And how about the glute-hamstroc raise? (love these)


the aforementioned exercises are good enough. what is the glute-hamstring raise?

[Frosty]

the aforementioned exercises are good enough. what is the glute-hamstring raise?

http://www.ppcchicago.com/exercises/exercise_dec04.php

[TPT]

http://www.ppcchicago.com/exercises/exercise_dec04.php


ah yes. of course. thank you. though not for gastroc-soleus because no load of the muscle is present.

[Frosty]

ah yes. of course. thank you. though not for gastroc-soleus because no load of the muscle is present.

I understand the soleus, but why wouldn't there be a load on the gastroc? If you plantar flexed the gastroc, sure, but if you kept a neutral foot position? I get sore in my gastroc from these.

[TPT]

I understand the soleus, but why wouldn't there be a load on the gastroc? If you plantar flexed the gastroc, sure, but if you kept a neutral foot position? I get sore in my gastroc from these.



though gastroc is a secondary knee flexor, the ankle has to be lengthened and shortened as well for the greatest stimulus. i suppose the load can be anterior tib dorsiflexing the ankle intead of an external load. the glute ham raise should be a final exercise after you have fully fatigued gastroc by lengthening the gastroc across both the knee and ankle in a close chain.

[fury-]

Magnesium before bed is good, but I think I have a better solution.

This is in addition to Mg before bed. Hard training guys just need more of it, plus Mg can help with sleep quality.

In the post-workout shake with high GI carbs, you take in a good form of magnesium, preferably mixed forms. 400mg or more if you tolerate it. The insulin will shuttle the magnesium into muscle tissue where you want it. Insulin is actually pretty important for having good intracellular magnesium stores, which is in turn important for handling insulin/glucose and other things. You want it in the cells, not outside, which is why insulin is very important to get it in the cells. Also the Mg will help to calm down the CNS after heavy lifting.

ok but when i just looked at the rda for Mg its like 400mg then its talking tolerable upper level supplemental intake of 350mg... that isnt much allowance for extra Mg... i mean if u say 400mg pw then like 300mg sleep... thats alot of mag in a day including a multi. I have never tried this much, seems excessive

[Frosty]

Good luck on keeping good magnesium status taking the RDA when training hard.

[fury-]

yah i knew u would say something like that, but it does seem like alot with taking a multi and sleep and training. Maybe i should just try it first cause i am definitely a fast twitch dominant athlete and maybe it would help me tolerate volume better cause somedaysi just dont seem to last through all my sets... and this is with rest.

[Frosty]

I doubt magnesium will all of a sudden make you handle volume better. But you're almost guaranteed to be magnesium deficient if you train hard. So you not only have higher requirements, but you have to restore levels as well.

The form of magnesium is important. Mg oxide is a waste of money. The "-ate" forms are better, but different ones target different tissues. Magnesium taurinate is a great form, and so is glycinate. Aspartate is another good form along with malate, orotate, and fumarate.