What is Rate of Force Development?
>> October 08, 2014
In short, Rate of Force Development (RFD) is the maximal rate of rise in muscle force, which is the speed of force production, or how quickly you can reach peak levels of force.
Look at these situations.
How fast can you move from 0.00 m to 3.00 m distance? ... The time taken can be heavily dependent on your RFD.
How quick can you jump from one point (position) to another point? Note that we are not talking about jump height or distance, but "how quick" ... That is depend on your RFD as well.
How good you are at the execution of "weak or slowest" part of an explosive activity, e.g. initial part of a sprint race (which is the slowest right?) ... Depend on your RFD.
There are many movements that occur very quickly, i.e. below 200 milliseconds. Ground contact in elite sprinters is around 0.100 s, javelin throw release takes about 0.180 s, and so on. These movements are largely influenced by your "ability", or the more specific term is "RFD".
Further enlightenment.
In a sprint race ...
a) your toughest opponent and yourself reacted very quickly (both at 0.13 s)
b) but he makes a gap very quickly
c) about 20 metres into the race, you found he was a metre in front
d) you managed to catch him at the end
e) both crosses the finish line together, you won by 0.001
... regardless the story of your race, he was superior than you at the start. How was it happen? he has a more efficient force application (because he has higher rate of force development) which ensured faster ground contact times at each step.
How do you measure Rate of Force Development?
This is not as simple as measuring your 1RM bench press. You need to have an extra careful with the method of measurement of RFD, including instruction (to ask performer to contract "as fast as possible" (during a 5-sec max voluntary contraction test) . Measurement is highly sensitive. When you use the isometric mid-thigh pull (with force plateform), the sampling rate can influence the "actual illustration" of force-time curve (the change in force with time). Thus, a sampling frequency of at least 500 hz may be required. However you can always have alternative. Field test such as movement time assessment can be applied, for instance the 5 m sprint time (although not that accurate, but still is very helpful). Other assessment such as bounding test can give a more representation for activities involving fast stretch shortening cycle (i.e. below 250 ms). Following is the illustration of 30 m bounding test.
1. Ready position on a box (30cm or 40cm).
2. Start by landing on the pre-determined start line (slightly in front, 50cm, of the box).
3. The time must start from first touch, stopped when body crosses line.
4. Determine the number of contact. If the last step involved only "half" step, you can say 0.5 (or 0.2 or 0.8 depend on your judgement).
5. Divide the number of contact with the time.
6. The higher ratio means the better.
The most important to remember in the bounding test is "consistency of measurement". You can also use electronic timing gate to reduce measurement errors, thus increases test sensitivity. Weight bag throw and vertical jump may also be used for RFD assessment. They have quite strong correlation with RFD value from the mid-thigh pull.
Final thought (but no way a final wrap-up of this particular topic!)
You can be very strong ... but this is not the quality that determine how quick you can move, or how fast you can accelerate ... it is how do you use the strength to move, sprint, jump or throw faster. Strength is the ability to produce force. Muscular strength must be further trained in order to become more powerful ... so one of the keys is to develop the explosive strength.
Explosive strength training ... the use of light to moderate equipment/tool or means (e.g. weightlifting snatch, plyometric, throwing exercises).
RFD assessment via the mid-thigh pull can also be used for training monitoring, diagnosis of muscular preparedness, fitness management, and so on.
Regardless of assessment means, please pay attention on consistency and test sensitivity.
Read more...
Malaysian Athletics Rankings 2014 - September 2
>> September 11, 2014
Malaysian Athletics Results 2014, Issue 7
>> August 31, 2014
Eugene OR (USA), 22-27 July 2014 “14th IAAF World Junior Championships”
-at Hayward Field !!
-overall position in bracket;
-results by all (3) Malaysians;
MEN
D T/1.75 (25): Q (14): Muhammad Irfan Shamsuddin (95) 57.74 (57.74, X, 53.23)
WOMEN
400m (23): ...5h2 Siti Nur Afiqah Abdul Razak (98) 56.54;
T J (24): ... Q (29). Kirthana Ramasamy (97) 12.32/+0.6 (12.07/-0.1, 12.32/+0.6, 11.94/ -1.4)
Ho Chi Minh (VIE), 25-27 July 2014 “21st Ho Chi Minh Track & Field Champs”
-regarded as Vietnam national open;
-national record achieved from women’s discus throw;
-results by all Malaysians;
MEN
400m (25): Kannathasan Subramaniam 47.83 (& 48.78 as 1h3);
110mh (25)/nwi: ...2. Rayzam Shah Wan Sofian 14.15 (& 14.87/-1.3 as 1h3) (finals won by Jamras Rittidet THA 14.00) ...
H J (25): ...5. Mohd Azly Ghazali (95) 2.04, ...8. Prakash Krishnan (95) 1.98, 9. Navin Raj Subramaniam 1.95;
WOMEN
D T (26): ... 3. Yap Jeng Tzan 47.79 NR
Glasgow (SCO), 27 Jul - 2 Aug “XX Commonwealth Games 2014”
-overall position shown in brackets;
-results by Malaysian athletes;
MEN
H J (28): ...Q (19=/23). Nauraj Singh Randhawa 2.06 (2.06/1, 2.11/x)
P V ( 1): ...9. Iskandar Alwi 5.00 (4.80/1, 5.00/2, 5.20/x)
H T (28): ...Q (18/20). Jackie Wong Siew Cheer 59.24 (58.19, 59.24, 58.26)
WOMEN
100mh (31): ...7h1 (19/20) Raja Nursheena Raja Azhar 14.30
H J (30): ...Q (23/24). Yap Sean Yee 1.71
Nanjing (CHN), 20-26 August 2014 “2nd Summer Youth Olympic Games”
-results by all (3) Malaysians;
BOYS
110mh 0.91 (20): ... Mohd Rizzua Haizad Muhamad (290397) DQ (R 162.7) (& 13.90/-0.6 as 1fC)
Notes: first 8 in heats for final A, the remainder would be in finals B or C based on times;
H J (20): ... Q. Norshafiee Mohd Shah (170997) 2.03 (1.90/1, 1.95/1, 1.99/2, 2.03/3, 2.07/x) ... (& 2.02 as 5fB (1.94/1, 1.98/3, 2.02/3, 2.05/x));
GIRLS
T J (25): ... 5. Kirthana Ramasamy (200197) 12.64/+1.0 (12.35/+0.7, 12.39/+0.1, 12.37/+0.3, 12.64/+1.0) ... (also Q 12.49/+0.6 (X, 12.49/+0.6, 12.47/+0.5, 11.04/-0.1) on 22nd);
Singapore (SIN), 23-24 Aug 2014 “76th Singapore Open Track and Field”
-best results by Malaysian athletes;
MEN
100m (24): ...4s2 Badrul Hisham Abdul Manap (97) 11.16/-0.5 (& 11.14/-0.8 as 4h3)
200m (23): ...3h3 Muhammad Azam Masri (96) 22.30/+0.8; ...3h1 Badrul Hisham Abdul Manap (97) 22.44/-0.1;
400m (24): ...4h1 Muhammad Azam Masri (96) 50.03
800m (23): ...6h1 Muhamad Nabil Mohd Nizar (96) 2:01.48
3000St (23): ...2. Ahmad Luth Hamizan 9:34.22
110mh (24)/-0.7: ...4. Rayzam Shah Wan Sofian 14.19 (& 14.26/-1.6 as 2h2) ... H1/-0.7: 4h1 Mohamad Rohaizad Jamil 14.93/-0.7, 5h1 Muhd Ajmal Aiman Hassan 15.23;
400mh (23): ...3. Muhamad Firdaus Musa 53.85, 4. Muhamad Firdaus Mazalan-II (Ked) 54.12;
H J (23): ...3. Nauraj Singh Randhawa 2.19 (2.06/1, 2.09/1, 2.11/1, 2.15/1, 2.19/3, 2.23/X) , ...6. Navin Raj Subramaniam 2.03, 7. Ahmad Najwan Aqra Hassaim 2.00, 8. Prakash Krishnan (95) 1.95, ...10. Mohd Azly Ghazali 1.95;
L J (23): ...7. Nik Lukmanul Hakim Nik Yahya 7.17/+1.6 (7.17/+1.6, 7.06/+0.8, 6.67/+0.1, 6.92/+0.7, 6.83/-0.8)
T J (24): Muhammad Hakimi Ismail 16.18/-1.2 (15.58/-2.4, 15.99/-2.3, 16.07/-1.5, 16.18/-1.2, 16.11/0.0, 15.98/-0.2), ...5. Nik Fariezal Erman Nik Ab Hadi (96) 14.55/-2.1, 6. Nik Lukmanul Hakim Nik Yahya 14.28/-1.6;
D T (24): Muhammad Irfan Shamsuddin (95) 52.53 (43.29, 47.13, 52.53, X, 47.54, X), ...10. Muhammad Afifi Najiy Ali (96) 36.36;
J T (23): ...5. Akid Chong Mohd Isham 63.93 (63.93, X, 61.81, X, 60.39, 59.60)
WOMEN
400m (24): ...2. Siti Nur Afiqah Abdul Razak (98) 55.11 (& 56.52 as 1h1), ...4. Nurul Faezah Asma Mazlan 58.04 (& 58.46 as 2h2), ... Fatin Faqihah Mohd Yusuf (96) DNS (& 60.15 as 5h1);
100mh (24)/+0.1:...5. Raja Nursheena Raja Azhar 14.33 (& 14.65/-1.1 as 3h2), ...7. Ku Munirah Ku Zamzuri 14.95 (& 15.17/-1.0 as 3h1) ...5h1 Aini Norazira Mohd Ali 15.37/-1.1;
H J (23): ...8. Yap Sean Yee 1.65 (1.65/2, 1.70/X), ...10. Nani Shahiera Zawawi (96) 1.50;
L J (23): ...2. Noor Amira Mohamad Nafiah 6.14/-0.1 (5.85/0.0, 6.01/+1.9, 5.73/0.0, 5.99/+1.9, 6.14/-0.1, X);
D T (24): ...3. Yap Jeng Tzan 44.98 (42.68, 44.16, 44.98, 42.27, 43.90, 43.90, 43.79), ...7. Choo Kang Ni 38.42;
J T (23): ...2. Siti Nur Nadiah Mohamad Osman 41.86 (X, 41.57, 39.15, 41.86, 41.01, 38.79), ...5. Nur Aqilah Amran (96) 35.61;
4x400m (23): ...2. Malaysia Team (????) 3:49.66
Kuantan, 23 August 2014 "48th Pahang Open Track and Field Championships"
-state championships (kejohahan olahraga terbuka negeri Pahang kali ke-48);
-in contrast with previous years, low performances’ standard achieved this year;
-all winners and best results as follows;
MEN
100m (+0.7) Mohd Izzuddin Yahaya 10.96, 2. Mohd Azhar Md Ismail 11.11, 3. Kannathanan
Subramaniam 11.11;
400m Luqmanul Hakim Khairul Akmal 51.23
800m Mohd Saddam Mohd Pitli 2:05.82
1500m Muhammad Syafiq Shamsul Bhari 4:14.45, 2. Devin Roy Vincent (99) 4:17.54
5000m Lim Kien Mau 16:42.48, 2. Royson Vincent (96) 17:13.37
110mh /+1.0: Zakaria Usup 16.75
400mh Quek Lee Yong (Sar/98) 54.96, 2. Mohd Adib Zulhusni Alet 56.21
H J Muhamad Ashraf Saipu Rahman 2.15
L J Luqman Hakim Mohd Ramlan (95) 7.10/+1.0
T J Yeap Poo Hock (Kel) 13.81/+0.8
S P Muhammad Malik Ahmad Tobias 12.86, 2. Ting Aik Hou 11.80, 3. Al Muzamsyar Arif
Abdullah (Ter) 11.55
10,000m W Premkumar Ramesh (Nse) 54:07.40
4x100m USPTN Terengganu Team (????) 45.56
4x400m SSMP Team (????) 3:38.10
WOMEN
100m (+1.0) Nea Maria Mattila (FINLAND/241199) 12.37, 2. Norris Foo (98) 12.60;
-heats: H2/+0.8: Norris Foo 12.80; H3/+0.7: Nea Maria Mattila 12.50
400m Herma Nurul Ain Yusuf 63.45
800m Nurul Izzati Suhaimi 2:36.20
1500m Noor Amelia Musa 5:10.88
5000m Lee Yan Ru (99) 24:19.18
100mh Norris Foo (98) 15.54/+0.8
400mh Nazatul Nadira Rusli (Ter) 73.07
H J Ravena Jazmine (Sel) 1.37
L J Nor Amyliena Ismail (Ter) 4.90
T J Lai Hui Shan 10.63/+1.0
S P Rahilah Othman 12.26
10,000m W Lee Yan Ru (99) 1:05:56
4x100m SSMP Team (????) 54.22
Putrajaya, 24 August 2014 “Mizuno Wave Run”
-selected results for 10km races (distance 9.95-10km ?) as follows;
MEN
1. Lili Suhairi Md Yang Ghazali 35:51, 2. Loh Chwan Chyin 36:10, 3. Genesen Subramaniam 36:33 (1st veteran 40+), 4. Jeffrey Ross (??) 36:45;
WOMEN
1. Adele Wong Li Peng 45:05, 2. Colleen Rosanna Augustin 45:56, 3. Tan Pei Leng 47:58 (1st veteran), 4. Wong Jia Yi 48:35, 5. Tan Mei Wai 48:43;
Acknowledgments
Heinrich Hubbeling
Results Pahang Open Track and Field 2014
>> August 25, 2014
Kuantan, 23 August 2014 "48th Pahang Open Track and Field Championships"
-state championships;
-kejohahan olahraga terbuka negeri Pahang kali ke-48
-all winners and best results as follows;
MEN
100m / +0.7: Mohd Izzuddin Yahaya 10.96, 2. Mohd Azhar Md Ismail 11.11, 3. Kannathanan Subramaniam 11.11;
400m: Luqmanul Hakim Khairul Akmal 51.23
800m: Mohd Saddam Mohd Pitli 2:05.82
1500m: Muhammad Syafiq Shamsul Bhari 4:14.45, 2. Devin Roy Vincent 4:17.54
5000m: Lim Kien Mau 16:42.48, 2. Royson Vincent 17:13.37
110mh / +1.0: Zakaria Usup 16.75
400mh: Quek Lee Yong (Sar) 54.96, 2. Mohd Adib Zulhusni Alet 56.21
H J: Muhamad Ashraf Saipu Rahman 2.15
L J: Lukman Hakim Ramlan 7.10/+1.0
T J: Yeap Poo Hock (Kel) 13.81/+0.8
S P: Muhammad Malik Ahmad Tobias 12.86, 2. Ting Aik Hou 11.80, 3. Al Muzamsyar Arif Abdullah (Ter) 11.55
10,000m W: Premkumar Ramesh (Nse) 54:07.40
4x100m: USPTN Terengganu Team (????) 45.56
4x400m: SSMP Team (????) 3:38.10
WOMEN
100m / +1.0: Nea Maria Mattila (FINLAND/241199) 12.37, 2. Norris Foo 12.60;
-heats: H2/+0.8: Norris Foo 12.80; H3/+0.7: Nea Maria Mattila 12.50
400m: Herma Nurul Ain Yusuf 63.45
800m: Nurul Izzati Suhaimi 2:36.20
1500m: Noor Amelia Musa 5:10.88
5000m: Lee Yan Ru (??) 24:19.18
100mh / +0.8: Norris Foo 15.54
400mh: Nazatul Nadira Rusli (Ter) 73.07
H J: Ravena Jazmine (Sel) 1.37
L J: Nor Amyliena Ismail (Ter) 4.90
T J: Lai Hui Shan 10.63/+1.0
S P: Rahilah Othman 12.26
10,000m W: Lee Yan Ru 1:05:56
4x100m: SSMP Team (????) 54.22