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(Peak_Power @ Sep. 06 2006,21:00)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">There's two different discussions going on in this thread, one about activation of MUs and another about diet. I'm just responding to the MU one.
Dan I don't want to argue with a moderator of this board, but I believe the abdominals have two nerve inputs, upper and lower, the upper being for spinal flexion and the other being posterior pelvic tilt.</div>
Actually, there's 3
MU, Fiber, BMR
Shot, argue all you want, won't hurt my feelings.
Ok, let's look at this then. 1. You are not speaking about the same thing I was, I said most human fibers are single innervated, 1 end plate per fiber. The known human muscles that aren't are the Lats, sartorius, gracilis and a newer recent report may include another but we don't need to look at it yet. Secondly in most human muscle the fibers run tendon to tendon and each fascicle is crossed by one band of endplates.
What you are talking about is some working showing that SEMG tests show that with incorrect pelvic tilit there is higher SEMG activity in the MU that correspond to upper RA MU recruitment versus lower. This a look at MU activity not what the muscle fibers themselves are doing.
So whether the endplates are more proximal or distal makes no difference as far as the entire fiber contracting, except of course where latency is concerned.
Lastly, I was talking about the single RA muscle not the entire abdomen musculature, which I point out that differing movements can change which muscles are recruited and which will play a more significant role in force.
1: Clark KM, Holt LE, Sinyard J.
Electromyographic comparison of the upper and lower rectus abdominis during
abdominal exercises.
J Strength Cond Res. 2003 Aug;17(3):475-83.
PMID: 12930172 [PubMed - indexed for MEDLINE]
2: Escamilla RF, Babb E, DeWitt R, Jew P, Kelleher P, Burnham T, Busch J,
D'Anna K, Mowbray R, Imamura RT.
Electromyographic analysis of traditional and nontraditional abdominal
exercises: implications for rehabilitation and training.
Phys Ther. 2006 May;86(5):656-71.
PMID: 16649890 [PubMed - indexed for MEDLINE]
3: Lehman GJ, McGill SM.
Quantification of the differences in electromyographic activity magnitude
between the upper and lower portions of the rectus abdominis muscle during
selected trunk exercises.
Phys Ther. 2001 May;81(5):1096-101.
PMID: 11319934 [PubMed - indexed for MEDLINE]
4: Karst GM, Willett GM.
Effects of specific exercise instructions on abdominal muscle activity during
trunk curl exercises.
J Orthop Sports Phys Ther. 2004 Jan;34(1):4-12.
PMID: 14964586 [PubMed - indexed for MEDLINE]
5: Mori A.
Electromyographic activity of selected trunk muscles during stabilization
exercises using a gym ball.
Electromyogr Clin Neurophysiol. 2004 Jan-Feb;44(1):57-64.
PMID: 15008027 [PubMed - indexed for MEDLINE]
6: Hildenbrand K, Noble L.
Abdominal Muscle Activity While Performing Trunk-Flexion Exercises Using the Ab
Roller, ABslide, FitBall, and Conventionally Performed Trunk Curls.
J Athl Train. 2004 Mar;39(1):37-43.
PMID: 15085210 [PubMed - as supplied by publisher]
7: Willett GM, Hyde JE, Uhrlaub MB, Wendel CL, Karst GM.
Relative activity of abdominal muscles during commonly prescribed strengthening
exercises.
J Strength Cond Res. 2001 Nov;15(4):480-5.
PMID: 11726260 [PubMed - indexed for MEDLINE]
8: Shields RK, Heiss DG.
An electromyographic comparison of abdominal muscle synergies during curl and
double straight leg lowering exercises with control of the pelvic position.
Spine. 1997 Aug 15;22(16):1873-9.
PMID: 9280023 [PubMed - indexed for MEDLINE]
9: Sarti MA, Monfort M, Fuster MA, Villaplana LA.
Muscle activity in upper and lower rectus abdominus during abdominal exercises.
Arch Phys Med Rehabil. 1996 Dec;77(12):1293-7.
PMID: 8976314 [PubMed - indexed for MEDLINE]
10: Vera-Garcia FJ, Grenier SG, McGill SM.
Abdominal muscle response during curl-ups on both stable and labile surfaces.
Phys Ther. 2000 Jun;80(6):564-9.
PMID: 10842409 [PubMed - indexed for MEDLINE]
11: Warden SJ, Wajswelner H, Bennell KL.
Comparison of Abshaper and conventionally performed abdominal exercises using
surface electromyography.
Med Sci Sports Exerc. 1999 Nov;31(11):1656-64.
PMID: 10589871 [PubMed - indexed for MEDLINE]
12: Guimaraes AC, Vaz MA, De Campos MI, Marantes R.
The contribution of the rectus abdominis and rectus femoris in twelve selected
abdominal exercises. An electromyographic study.
J Sports Med Phys Fitness. 1991 Jun;31(2):222-30.
PMID: 1836517 [PubMed - indexed for MEDLINE]
13: Bird M, Fletcher KM, Koch AJ.
Electromyographic comparison of the ab-slide and crunch exercises.
J Strength Cond Res. 2006 May;20(2):436-40.
PMID: 16686576 [PubMed - in process]
14: Moraes AC, Bankoff AD, Almeida TL, Simoes EC, Rodrigues CE, Okano AH.
Using weights in abdominal exercises: electromyography response of the Rectus
Abdominis and Rectus Femoris muscles.
Electromyogr Clin Neurophysiol. 2003 Dec;43(8):487-96.
PMID: 14717029 [PubMed - indexed for MEDLINE]
(Peak_Power @ Sep. 06 2006,21:00)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">There's two different discussions going on in this thread, one about activation of MUs and another about diet. I'm just responding to the MU one.
Dan I don't want to argue with a moderator of this board, but I believe the abdominals have two nerve inputs, upper and lower, the upper being for spinal flexion and the other being posterior pelvic tilt.</div>
Actually, there's 3
MU, Fiber, BMR
Shot, argue all you want, won't hurt my feelings.

Ok, let's look at this then. 1. You are not speaking about the same thing I was, I said most human fibers are single innervated, 1 end plate per fiber. The known human muscles that aren't are the Lats, sartorius, gracilis and a newer recent report may include another but we don't need to look at it yet. Secondly in most human muscle the fibers run tendon to tendon and each fascicle is crossed by one band of endplates.
What you are talking about is some working showing that SEMG tests show that with incorrect pelvic tilit there is higher SEMG activity in the MU that correspond to upper RA MU recruitment versus lower. This a look at MU activity not what the muscle fibers themselves are doing.
So whether the endplates are more proximal or distal makes no difference as far as the entire fiber contracting, except of course where latency is concerned.
Lastly, I was talking about the single RA muscle not the entire abdomen musculature, which I point out that differing movements can change which muscles are recruited and which will play a more significant role in force.
1: Clark KM, Holt LE, Sinyard J.
Electromyographic comparison of the upper and lower rectus abdominis during
abdominal exercises.
J Strength Cond Res. 2003 Aug;17(3):475-83.
PMID: 12930172 [PubMed - indexed for MEDLINE]
2: Escamilla RF, Babb E, DeWitt R, Jew P, Kelleher P, Burnham T, Busch J,
D'Anna K, Mowbray R, Imamura RT.
Electromyographic analysis of traditional and nontraditional abdominal
exercises: implications for rehabilitation and training.
Phys Ther. 2006 May;86(5):656-71.
PMID: 16649890 [PubMed - indexed for MEDLINE]
3: Lehman GJ, McGill SM.
Quantification of the differences in electromyographic activity magnitude
between the upper and lower portions of the rectus abdominis muscle during
selected trunk exercises.
Phys Ther. 2001 May;81(5):1096-101.
PMID: 11319934 [PubMed - indexed for MEDLINE]
4: Karst GM, Willett GM.
Effects of specific exercise instructions on abdominal muscle activity during
trunk curl exercises.
J Orthop Sports Phys Ther. 2004 Jan;34(1):4-12.
PMID: 14964586 [PubMed - indexed for MEDLINE]
5: Mori A.
Electromyographic activity of selected trunk muscles during stabilization
exercises using a gym ball.
Electromyogr Clin Neurophysiol. 2004 Jan-Feb;44(1):57-64.
PMID: 15008027 [PubMed - indexed for MEDLINE]
6: Hildenbrand K, Noble L.
Abdominal Muscle Activity While Performing Trunk-Flexion Exercises Using the Ab
Roller, ABslide, FitBall, and Conventionally Performed Trunk Curls.
J Athl Train. 2004 Mar;39(1):37-43.
PMID: 15085210 [PubMed - as supplied by publisher]
7: Willett GM, Hyde JE, Uhrlaub MB, Wendel CL, Karst GM.
Relative activity of abdominal muscles during commonly prescribed strengthening
exercises.
J Strength Cond Res. 2001 Nov;15(4):480-5.
PMID: 11726260 [PubMed - indexed for MEDLINE]
8: Shields RK, Heiss DG.
An electromyographic comparison of abdominal muscle synergies during curl and
double straight leg lowering exercises with control of the pelvic position.
Spine. 1997 Aug 15;22(16):1873-9.
PMID: 9280023 [PubMed - indexed for MEDLINE]
9: Sarti MA, Monfort M, Fuster MA, Villaplana LA.
Muscle activity in upper and lower rectus abdominus during abdominal exercises.
Arch Phys Med Rehabil. 1996 Dec;77(12):1293-7.
PMID: 8976314 [PubMed - indexed for MEDLINE]
10: Vera-Garcia FJ, Grenier SG, McGill SM.
Abdominal muscle response during curl-ups on both stable and labile surfaces.
Phys Ther. 2000 Jun;80(6):564-9.
PMID: 10842409 [PubMed - indexed for MEDLINE]
11: Warden SJ, Wajswelner H, Bennell KL.
Comparison of Abshaper and conventionally performed abdominal exercises using
surface electromyography.
Med Sci Sports Exerc. 1999 Nov;31(11):1656-64.
PMID: 10589871 [PubMed - indexed for MEDLINE]
12: Guimaraes AC, Vaz MA, De Campos MI, Marantes R.
The contribution of the rectus abdominis and rectus femoris in twelve selected
abdominal exercises. An electromyographic study.
J Sports Med Phys Fitness. 1991 Jun;31(2):222-30.
PMID: 1836517 [PubMed - indexed for MEDLINE]
13: Bird M, Fletcher KM, Koch AJ.
Electromyographic comparison of the ab-slide and crunch exercises.
J Strength Cond Res. 2006 May;20(2):436-40.
PMID: 16686576 [PubMed - in process]
14: Moraes AC, Bankoff AD, Almeida TL, Simoes EC, Rodrigues CE, Okano AH.
Using weights in abdominal exercises: electromyography response of the Rectus
Abdominis and Rectus Femoris muscles.
Electromyogr Clin Neurophysiol. 2003 Dec;43(8):487-96.
PMID: 14717029 [PubMed - indexed for MEDLINE]