duldog
Free Rider
beauty is in the eyes of the beerholder
Posts: 325
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Post by duldog on Oct 26, 2004 8:11:55 GMT 8
a friend of mine rides a rigid bike for commuting and he complains of lower back pain while riding. he is using a specialized body geometry saddle on his 17" marin palisades trail bike and his handle bar is 1" lower than his seat. he is 5'7"tall and 160 lbs heavy. we tried to lower his saddle pero ganun pa rin ang complaints nya.
any help will be greatly appreciated.tnx!
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Post by warlock^_^ on Oct 26, 2004 8:30:54 GMT 8
What is the size of the Stem he's using? the Top tube is only 21 3/4"(2004 model), its not that long but then again maybe your friend have shorter torso. But if its an older model 17"; 22 1/2" (2003) well thats a bit long. You guys can try fiddling with the stem sizes and angle, maybe the current setup makes him to lean too much thus causing the lower back pain. Try dealing with the bikeshop where he got the bike to try out various stems to spot on where he is more comfortable.
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duldog
Free Rider
beauty is in the eyes of the beerholder
Posts: 325
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Post by duldog on Oct 26, 2004 9:19:50 GMT 8
tnx!
the stem he is using (the best i can remember) is about 4.5" na medium rise and is using a 2" riser bar. is this too long?
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Post by warlock^_^ on Oct 26, 2004 9:26:16 GMT 8
tnx! the stem he is using (the best i can remember) is about 4.5" na medium rise and is using a 2" riser bar. is this too long? 4.5"? thats about 114.3mm... try using shorter stems 90mm or 100mm. Typical longest stem used in MTB is 120mm, so with that size, its long.
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Post by woofers on Oct 26, 2004 9:47:59 GMT 8
Agree with warlock, the stem is probably too long. Lowering the saddle will not help. Try watching him ride and eyeball if he's too stretched out.
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Post by gulliver on Oct 26, 2004 10:09:28 GMT 8
you can also advise him to get off the saddle when riding over bumps...to vary his riding position every now and then....to lower the nose of his saddle a bit to place more weight on his shoulders and arms rather than on his butt. he can also adjust the spacers on his steerer tube to raise his stem and consequently his bar. his 2" riser bar, is it angled away or towards the rider? maybe he needs to make sure its towards the latter too. also, while biking, can your friend straighten out his back comfortably? like maybe somewhere at least 70-80 degrees relative to the ground? like in more of a trail riding position? if not, his bar is probably too far forward as suggested by warlock...as in a XC race position...stressful sa likod yun lalo na pag dehins masyadong flexible yung katawan. does he wear a backpack while commuting? those things can be murder if too heavy or improperly fitted and you're leaning forward.
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Post by gulliver on Oct 26, 2004 10:27:46 GMT 8
just to add... i'm 5'8" and used to ride a 17" HT frame w/ a 90mm x 5 degree stem and a 2" riser bar...would often get back pains on ordinary road rides. i changed bikes, got a 15.5" HT frame, used a 100 mm x 5 degree stem w/ a 1" riser bar...and the back pains disappeared. this frame's effective top tube length was also about an inch shorter than the previous hardtail. it takes some experimentation to get your proper fit on your own. good if you can do it at the shop, but for me, things didn't show up till i had several hours on the bike to recap, what warlock and woofer are saying, is probably the first thing you need to change, your stem length. a 110mm stem length according to some people i've spoken with, would be good for riders 5'9"- 6'3"...not sure if that's a hard and fast rule but think it's a good indication of what your stem length should not be
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Post by jr on Oct 26, 2004 10:52:17 GMT 8
Just may add.. Based on his height .. he should use 16" frame. The stem would be 100 or 110 m. If he use a riser bar he should use 0" or 5" rise.
Lower back pain could be coming from something else. Biking sometimes will irritet more. The other cause is weak lower back muscles and heavy stomach (malaki and tiyan) but this will vary to person to person because I excercised my lower back and to lots of set up but have same similar problem just ignoring it.
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Post by minotaur on Oct 26, 2004 10:59:12 GMT 8
I think we all have the same thing in mind... ;D ;D ;D
Mountain bicyclists are subject to various traumatic and overuse injuries. Traumatic injuries range from minor abrasions and contusions to wrist fractures, shoulder injuries, and concussions. Helmet use is important in preventing serious head trauma. Many overuse injuries stem from improper bike fit, anatomic malalignments, and training errors. Treatment includes adjustments to the bike and modification of training habits.
Overuse injuries in off-road cyclists are related to interactions between the cyclist's body, the bicycle, and the terrain on which they ride. The effects of anatomic variations and small errors in bike fit are magnified by long hours spent riding and by highly repetitive lower-extremity motions. A combination of these factors is usually responsible for overuse injuries of the lower extremity.
Training errors frequently contribute to overuse injuries. The abundance of hills available for off-road riding can easily tempt a rider to push beyond his or her established level of conditioning, especially early in the season. Common training errors include inadequate preseason conditioning, riding in too high a gear by overrelying on the large chainring, and suddenly increasing mileage, hill climbing, or riding intensity.
Common Mountain Biking Overuse Injuries, Bicycle-Related Causes, and Suggested Adjustments
Low-back pain due to 1. Excessive vibration --> Use wider tires and/or lower inflation pressure; consider adding or adjusting front suspension 2. Incorrect reach --> Check upper-body position; consider decreasing reach if cyclist is too far forward or if pain is related to extension on physical examination; increase reach if upper body is crowded or if pain is related to flexion on exam 3. Incorrect saddle position --> Ensure proper saddle position (see "How to Fit a Mountain Bike" by Mad_doc) 4. Low-back inflexibility --> Raise handlebar or change to upright handlebar
Ref: Mountain Biking Injuries: Fitting Treatment to the Causes: Robert Kronisch, M.D., The Physician and Sports Medicine - VOL. 26 - NO. 23 –March 98
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Post by weekendrider on Oct 26, 2004 11:19:48 GMT 8
What kind of work is he doing? Just curious, if it is from biking or work related.
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Post by warlock^_^ on Oct 26, 2004 11:38:27 GMT 8
What kind of work is he doing? Just curious, if it is from biking or work related. or from somewhere else *wink* *wink* *wink*
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Post by gulliver on Oct 26, 2004 13:26:30 GMT 8
or from somewhere else *wink* *wink* *wink* and if he has calloused knees, this might be something worth re-examining....like lying prone on his back instead ;D
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duldog
Free Rider
beauty is in the eyes of the beerholder
Posts: 325
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Post by duldog on Oct 26, 2004 15:13:29 GMT 8
thanks for all the ideas! its very informative and i'll tell my friend asap. my friend rides about 12kms (one way) a day and he works as an elementary grades teacher kaya magaan lang trabaho, with a slight bulge and regularly does bed exercise ung repetitive horizontal hip thrusts kaya calloused knees is not a problem ;D thanks a million!
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Post by mad_doc on Oct 26, 2004 17:39:50 GMT 8
warlock gulli and jr have got the riding aspect down.... minotaur has the medical side covered.... soooo since it is not work related..... maybe the vertical thrust technique is to blame.... ;D looks like we are all a bit horny these days maybe you guys could also answer the new poll he he
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Post by weekendrider on Oct 27, 2004 9:49:16 GMT 8
warlock gulli and jr have got the riding aspect down.... minotaur has the medical side covered.... soooo since it is not work related..... maybe the vertical thrust technique is to blame.... ;D looks like we are all a bit horny these days maybe you guys could also answer the new poll he he That's a good one, doc. That could be it. Vertical thrust. hehehehe.
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duldog
Free Rider
beauty is in the eyes of the beerholder
Posts: 325
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Post by duldog on Nov 3, 2004 10:25:26 GMT 8
i informed my friend about your suggestions and he promptly replaced his stem to 70cm (orig-100cm pala) with same angle and now he says his back pain is gone even after a good 3hr ride. we are very thankful to you guys! maraming salamas sa mga ideas nyo! mabuhay ang pinoymtbiker!
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Post by gulliver on Nov 3, 2004 13:01:13 GMT 8
i informed my friend about your suggestions and he promptly replaced his stem to 70cm (orig-100cm pala) with same angle and now he says his back pain is gone even after a good 3hr ride. we are very thankful to you guys! maraming salamas sa mga ideas nyo! mabuhay ang pinoymtbiker! glad to know the guys were able to help your friend out
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Post by jr on Nov 3, 2004 13:05:06 GMT 8
glad to know the guys were able to help your friend out Yap.. that's good to hear and help someone.
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