Fiber Architecture(Struktur serat) Fusiform (parallel) Serat otot bergerak secara longitudinal Umumnya serat otot tidak merentang sepanjang otot. (generally fibers do not extend the entire length of muscle)

Fiber Architecture Pennate Serat bergerak diagonal terhadap urat daging (fibers run diagonal to the tendon (short fibers))

Fusiform vs. Pennate fusiform pennate Keuntungan: sarcomeres berada dalam rangkian jadi kecepatan maksimal dan dan ROM meningkat. Kerugian: termasuk rendah # dari parallel sarcomeres jadi tenaga rendah pennate Keuntungan : meningkatkan # dari sarcomeres ke parallel, sehingga PCSA dan tenaga meningkat Kerugian : mengurangi ROM and penurunan kecepatan

Pennation Angles Muscle Pennation Angle (deg) gastrocnemius 10-25 soleus 15-30 tibialis anterior 5-10 biceps femoris Catatan : sudut pennation mungkin meningkat seiring dengan peningkatan tegangan otot. (These pennation angles may increase as the muscle tension increases.) From: Multiple Muscle Systems, Winters and Woo

Fiber Type Comparison Type I Type IIa Type IIb Shortening Speed slow fast Energy System oxidative oxidative, glycolytic Size small large Force per unit of mass low high Aerobic Capacity medium Anaerobic Fatigability) Perhatikan bahwa serat tipe I adalah yang terkecil, karena mengacu pada prinsip ukuran, mereka diterima pertama kali.(Note that type I fibers are smallest therefore, according to the size principle, they are recruited first).

Fiber Types (Jenis Serat) Semua serat dalam sebuah unit motor adalah jenis yang sama.(all fibers within a motor unit are of the same type) Dalam sebuah otot ada dari gabungan jenis serat. (within a muscle there is a mixture of fiber types) Jenis serat mungkin berubah dengan latihan. Penerimaan yang diatur (recruitment is ordered) type I serat diterima pertama (awal terkecil, sentakan neuron rendah) fibers recruited 1st (lowest threshold, slow twitch neurons) type IIa serat diterima kedua (awal medium, sentakan perlawanan neuron lelah cepat)  fibers recruited second (medium threshold, fast twitch fatigue resistant neurons) type IIb serat diterima terakhir (awal tertinggi, sentakan neuron lelah cepat )  fibers recruited last (highest threshold, fast twitch fatigable neurons)

Fiber Type Distribution (Distribusi Jenis Serat) Muscle Fiber Type (%SO, %FOG, %FG) vastus medialis 50, 15, 35 erector spinae 58, - ,42 soleus 80, - , 20 orbicularis oculi 15, - , 85 From: Multiple Muscle Systems, Winters and Woo

Force and Fatigue (Tenaga dan Kelelahan) Twitch Force MU1 (type IIb) MU2 (type IIa) MU3 (type I) Time (short duration) Tetanic Force MU1 MU2 MU3 Time (long duration) Latash, p44, MU1-fastest and strongest, MU3-smallest and slowest

Force – Velocity Relationship (Hubungan tenaga-tegangan) Catatan: Diperuntukkan bagi kontraksi maksimum pada jarak relaksasi otot.(This is for a maximal contraction at the resting length of the muscle). v < 0 (eccentric) v > 0 (concentric) force velocity of contraction (kecepatan kontraksi) v=0 (isometric)

Hubungan Kekuatan-Kecepatan (Power – Velocity Relationship) F Power (F*v) v 30% vmax

Struktur dan Kekuatan/Kecepatan (Architecture and Force/Velocity) Force (N) Muscle Velocity (cm/s) long fibers short fibers Force (N) Muscle Velocity (cm/s) large PCSA small PCSA From Lieber, p. 69

Active Length-Tension L0= jarak relaksasi(tidak berkontraksi maupun merentang) resting length (neither contracted nor stretched) Tension Length L0

Panjang-Tegangan (Length-Tension) Catatan: Diperuntukkan bagi kontraksi isometerik maksimum. physiological range combined Tension active passive Length L0

Struktur dan Panjang/Tegangan (Architecture and Length/Tension) Force (N) Muscle Length (cm) long fibers short fibers Force (N) Muscle Length (cm) large PCSA small PCSA From Lieber, p. 69

Jumlah sendi yang dilewati. (Number of Joints Crossed) uniarticular or monoarticular – otot melintasi tulang sendi, jadi mempengaruhi gerakan hanya pada 1 tulang sendi.(the muscle crosses 1 joint, so it affects motion at only 1 joint) biarticular and multiarticular (multijoint) – otot melintasi 2 atau lebih sendi, menghasilkan gerakan melintasi banyak sendi.(the muscle crosses 2 (bi) or more (multi) joints, so it can produce motion across multiple joints)