Advertise on Bikeforums.net



User Tag List

Results 1 to 19 of 19
  1. #1
    Senior Member fueledbymetal's Avatar
    Join Date
    May 2007
    Location
    St. Mary's City, MD
    My Bikes
    Cannondale SuperSix & CAAD9, Singlespeed Seven
    Posts
    212
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    HRM has 30 bpm fluctuations?

    I just bought my first HRM, the Sigma Sport Coach Heart Rate Monitor, and I tried it out while running yesterday (I haven't tried it on my bike yet). It read my resting pulse consistently, but I noticed while I was running that would jump back & forth between 128 and 158 bpm while I was running at an even pace along a level stretch. Is this normal or is the HRM to blame?

  2. #2
    Triathlon in my future??? flip18436572's Avatar
    Join Date
    Jun 2007
    Location
    Southwest Iowa
    My Bikes
    Junk, that is why I am here. :-)
    Posts
    2,193
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Your heart rate will not change that much from my experience. I have had problems with a treadmill giving me a false reading while wearing the monitor, as it actually doubled the heart rate for about 30 seconds. I was using my watch at the same time, that is how I know it was showing double. Never had the problem again.
    2007 Jamis Ventura Comp
    2006 Jamis Explorer 2.0
    2000 Specialized Hardrock (bought used)
    Swim, Bike, Run and sounds like fun

  3. #3
    Throw the stick!!!! LowCel's Avatar
    Join Date
    Apr 2003
    Location
    Charleston, WV
    My Bikes
    GMC Denali
    Posts
    17,586
    Mentioned
    11 Post(s)
    Tagged
    1 Thread(s)
    Definitely not normal, I would contact where you purchased it from and check on an exchange.
    I may be fat but I'm slow enough to make up for it.

  4. #4
    sch
    sch is offline
    Senior Member
    Join Date
    May 2003
    Location
    Birmingham. AL
    Posts
    2,589
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    HRM can be expected to do this. If they are monitering the electrical activity
    of the heart, they can not be expected to disregard the electrical activitiy of
    other muscles in the vicinity of the sensors, so when running you are hyper
    ventilating and the chest/pectoral and shoulder muscles are all very active
    contributing electrical inputs sometimes counted as a heart beat. In addition
    the skin contact of the sensor can intemittently loosen and tighten under
    running stress as your chest changes shape while breathing and pumping the
    arms. Result is missed beats and missed counts. Changing the HRM will not
    change these reasons for variable counts. Even hospital grade moniters will
    vary 5% or more on someone laying quietly in bed and can bounce the trace
    from the bottom of the screen to the top in response to arm or chest motion
    such as adjusting the blanket, or reaching for a drink.

  5. #5
    Senior Member Terex's Avatar
    Join Date
    Jan 2005
    Location
    Jersey - outside the bibs.
    Posts
    3,457
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    That may well be true, but... In the past (before my battery died for the millionth time) when I would download my Polar HR data to a scatter-o-gram, it was extremely rare for me to see any outlying data points. I'd also occasionally look at beat-by-beat tables, and only rarely saw the types of outliers you describe. It may more likely be electrical interference (overhead lines, other people with monitors, etc.).

    Do you exercise with others who may be using HRM's? Do you exercise in the area of high tension lines? That, or a defective monitor, is more likely the cause of your problem.
    "It could be anything. Scrap booking, high-stakes poker, or the Santa Fe lifestyle. Just pick a dead-end and chill out 'till you die."

  6. #6
    Senior Member fueledbymetal's Avatar
    Join Date
    May 2007
    Location
    St. Mary's City, MD
    My Bikes
    Cannondale SuperSix & CAAD9, Singlespeed Seven
    Posts
    212
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Terex View Post
    Do you exercise with others who may be using HRM's? Do you exercise in the area of high tension lines? That, or a defective monitor, is more likely the cause of your problem.
    Thanks for input so far. I was running solo nowhere near any power lines.

  7. #7
    Senior Member
    Join Date
    Jul 2003
    Location
    Boulder, CO
    Posts
    7,210
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    flapping nylon clothing can also cause weird readings. my garmin 305 frequently reads around 230bpm when I'm descending wearing a particular (flappy) jacket.
    ...

  8. #8
    Senior Member
    Join Date
    Oct 2004
    Posts
    251
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    try turning on an off if it happens again or make sure good contact with your skin.

    if it is not coded you can get someone elses readings at times
    powerlines and in TX the electric farm fences mess me up

    it should not jump around at all, just have some delays on intervals.

  9. #9
    just another gosling Carbonfiberboy's Avatar
    Join Date
    Feb 2007
    Location
    Everett, WA
    My Bikes
    CoMo Speedster 2003, Trek 5200, CAAD 9, Fred 2004
    Posts
    8,028
    Mentioned
    3 Post(s)
    Tagged
    1 Thread(s)
    Nylon and some polyester garments generate spurious readings. Try wearing different tops. Lick the HR transmitter's contact patches thoroughly before putting it on. Try smearing some saliva on them if you are getting spurious readings and not sweating. Sweat usually takes care of it. Needs to be an electrolyte. Tap water doesn't work. Duh-Dum cream is available to assist in getting good contact, but is usually unnecessary.

  10. #10
    Senior Member fueledbymetal's Avatar
    Join Date
    May 2007
    Location
    St. Mary's City, MD
    My Bikes
    Cannondale SuperSix & CAAD9, Singlespeed Seven
    Posts
    212
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Carbonfiberboy View Post
    Try smearing some saliva on them if you are getting spurious readings and not sweating. Sweat usually takes care of it. Needs to be an electrolyte. Tap water doesn't work.
    Thanks - I'll try this!

  11. #11
    Getting Less Chunky ChunkyB's Avatar
    Join Date
    Oct 2007
    My Bikes
    2004 Raleigh SuperCourse
    Posts
    973
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Put some of that HRM gel on the contacts. Maybe if there's not good enough contact (no moisture, strap too loose) it can give false numbers like that.

    I don't usually have any problem because it kind of just get squeezed under my man breasts. There's usually plenty of moisture down there.

  12. #12
    Senior Member
    Join Date
    Feb 2006
    Posts
    1,564
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    no. it should be accurate. the fix is listed above but


    make sure the strap is tight

    spit on finger, rub spit on the contacts of the strap
    ----
    overhead high voltage wires, or transformers can cause it to go wacky, so
    make sure this isn't happening under wires or near transformers within 30 feet

  13. #13
    Senior Member
    Join Date
    Feb 2005
    Location
    No Va but ride also in So Md
    My Bikes
    Cervelo SLC-SL, Guru Photon, Waterford, Specialized CX
    Posts
    8,258
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    I have similar problems, especially when the humdity is low and/or a breeze is there to dry up moisture. It never happens in heat, humidity, and after I really warm up sweating. As someone else said, nylon and synthetic material makes it worse. Also some materials generate statisc electricity. Garmin says to dampen your jershey before going out. Also somone else mentioned use of geals or saliva on the chest pads. I usually do that verey time.
    You're just trying to start an argument to show how smart you are.

  14. #14
    King of the Plukers Spreggy's Avatar
    Join Date
    May 2007
    Location
    On the bus.
    Posts
    873
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I would compare it to how it does on the bike, where there isn't the bounce factor. I'll bet there's your answer.

  15. #15
    Senior Member Richard Cranium's Avatar
    Join Date
    Jun 2002
    Location
    Deep in the Shawnee Forest
    My Bikes
    LeMond - Gunnar
    Posts
    2,786
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    but I noticed while I was running that would jump back & forth between 128 and 158
    Maybe a loose chest strap? But if the numbers are not "sticking" -and then jumping 30 bpm - there's something else wrong.

    All the HRMs I know of would be displaying plenty of numbers in between 128 and 158 - not just jumping 30 beats. So if you see stuff like 128 138 146 140 150 156 150 140 136 - you may have some other wacky stuff going on with your heart.........

  16. #16
    Senior Member George's Avatar
    Join Date
    Jul 2006
    Location
    Katy Texas
    My Bikes
    Specialized Roubaix - Look 566 - Jamis Coda Elite
    Posts
    5,251
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    It sounds like your losing contact. They sell lubricating gel at the store, just put a little on and that should do it.
    George

  17. #17
    newbie rider
    Join Date
    Aug 2007
    Location
    Houston, TX
    Posts
    481
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Carbonfiberboy View Post
    Tap water doesn't work. Duh-Dum cream is available to assist in getting good contact, but is usually unnecessary.
    why wouldn't tap water work? in HS a chem experiment we did was involving the electrical conductivity of tap water. by trying using the tap water as a conductor between two electrodes on a light bulb comparing it to distilled water and the tap water worked.

  18. #18
    Getting Less Chunky ChunkyB's Avatar
    Join Date
    Oct 2007
    My Bikes
    2004 Raleigh SuperCourse
    Posts
    973
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by mista_chewey View Post
    why wouldn't tap water work? in HS a chem experiment we did was involving the electrical conductivity of tap water. by trying using the tap water as a conductor between two electrodes on a light bulb comparing it to distilled water and the tap water worked.
    I don't think it's as much a problem of conductivity, it's more a problem of having continuous contact. The water would make a very thin layer, but maybe the lotion can provide a thicker layer between the the chest (or back) and the strap. Anyways, maybe I'm way off, but I think it's another factor to keep in mind.

  19. #19
    newbie rider
    Join Date
    Aug 2007
    Location
    Houston, TX
    Posts
    481
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    ^^ that makes sense
    didnt think about water drying off haha

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •