Month: August 2015

  • Ice or Heat ??

    August 31, 2015
    Written by Dr. Aron Low, PT, DPT, MEd, ATC

    Ice or heat?  As a physical therapist, that is one of the questions I hear more than any other.  Frequently, my patients are surprised by my answer, which is “Which one makes you feel better?”  There are a ton of reasons as to why this is my answer, but most important to me is that if it makes you feel good, you should utilize it, especially if it doesn’t have any negative side effects.

    First, I want to go over a few myths about both Ice and Heat, and give you some information about both that might help you pick the treatment that is best for you.

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    First Myth: Ice stops or prevents inflammation/ decreases swelling.  Ice is a thermal modality that works by removing heat through abstraction (removal of heat from higher temperature to an object of lower temperature).  Heat transfer can occur by way of conduction, convection, or evaporation.  Conduction is the transfer of heat from a warmer surface to a colder surface by means of physical contact.  Convection is the transfer of heat from the body to the air or fluid moving around it.  Evaporation is the heat lost by an object through the vaporization from the application of liquids that evaporate on contact with the skin, releasing heat to the air around the skin.  The use of ice results in physiologic changes to body systems and structures.  Blood flow is decreased to due to vasoconstriction (closing off of blood vessels) from sympathetic adrenergic activity, and capillary and cellular membrane permeability is decreased, allowing less fluid to move into interstitial space (area between cells). Cellular metabolism is decreased (decreasing the need for oxygen and reducing secondary hypoxia or injury due to lack of oxygen). Pain threshold increases due to decreased nerve conduction velocity and blockage of synaptic activity (your nerves do not transmit information quickly anymore, meaning pain is decreased.)  Muscle spasm will also be reduced by the decrease in alpha motor neuron activity, inhibited firing of type II afferent muscle spindles, and interruption of the pain-spasm cycle.

    There is limited evidence that the use of cryotherapy can decrease edema (swelling).  Some studies are showing that when used directly following surgery, there is a decrease in pain, improved ROM, and better adherence to physical therapy, but there is not a decrease in circumferential measurements compared to those who are not treated with cryotherapy.  In essence, using ice does not make the swelling going down, especially if you stand back up, as gravity will pull fluid right back to where you MAY have reduced it.

    Uses: pain modulation, decreasing secondary hypoxic injury, muscle spasm reduction.

    Next Myth: Heat will increase swelling.  Using heat, another form of thermotherapy , results in the increase in temperature of the skin due to some external source that is hotter than the temperature of the skin. Physiologic changes to human tissue when heated include increased cellular metabolism, increased blood flow and tissue oxygenation secondary to vasodialation, and increase tissue (collagen) extensibility, meaning it is “stretchier”.  Heat therapy can also create relaxation, which can reduce muscle spasms and even decrease pain.  Using heat does not increase arterial blood flow and restrict venous blood flow, in fact, it is more likely to do the opposite.  Since arterial blood flow usually occurs deeper than the structures you are trying to heat, only the venous blood vessels will dilate, causing increased blood flow FROM the site of injury, taking with it all the waste products from healing.

    Uses: prior to stretching/exercise, increase tissue temperature, decrease pain/muscle spasm, increase collagen extensibility, increase peripheral blood flow.

    Sources:
    Bleakley C, McDonough S, and MacAuley D.  The use of ice in the treatment of acute soft tissue injury: a systematic review of randomized control trials. American Journal of Sports Medicine. 2004; 32(1); 251-61.

    Enwemeka CS, Allen C, Avila P, Bina J, Konrade J, and Munns, S.  Soft tissue thermodynamics before, during, and after cold pack therapy.  Medicine and Science in Sport and Exercise. 2002; 34(1):45-50.

    Cohn BT, Draeger RI, Jackson DW.  The effects of cold therapy in the postoperative management of pain in patients undergoing anterior cruciate ligament reconstruction.  American Journal of Sports Medicine.1989; 17(3): 344-9.

    Merrick MA, Rankin JM, Andres FA, Hinman CL.  A preliminary examination of cryotherapy and secondary injury in skeletal muscle. Medicine and Science in Sport and Exercise.  1999; 31(11): 1516-21.

    Knight CA, Rutledge CR, Cox ME, Acosta M, and Hall SJ.  Effect of superficial heat, deep heat, and active exercise warm-up on the extensibility of the plantar flexorsPhysical Therapy.  2001; 81(6): 1206-1214.

    Lentell G, Hetherington T, Eagan J, Morgan M. The use of thermal agents to influence the effectiveness of a low-load prolonged stretch. JOSPT.  1992; 16(5):200-207.

  • Stay safe in the heat!

    August 14, 2015

    Tips on how to avoid over-heating when exercising outside
    By: Traci Bacon

    Everyone loves to get outside and be active during the summer months when the sun is shining and the heat temperatures are rising. However, exercising in hot weather can put extra stress on your body! You can prevent heat-related symptoms by taking basic precautions and being proactive when having fun in the sun.
    Be aware of warning signs of over-heating:
    • Muscle cramping
    • Abnormal heart rhythms
    • Weakness/ loss of coordination
    • Dizziness/light headedness/ fainting
    • Headache
    • Fatigue
    • Visual problems
    • Confusion
    • Excessive sweating
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    How to prevent symptoms of over-heating: 
    Plan your workouts/time in the heat:
    Pay attention to the weather and plan your outdoor activities based on the temperature; for example; long runs early or later in the day (avoiding mid day sun). Be aware of heat alerts in your area!Back- up plan:
    We all know the weather channel is not 100% accurate, so have a back-up plan. Whether this includes indoor exercise options if it is too hot out, or planning runs based on available water stops.  Rest in shady areas.

    Know your fitness level:
    Before pushing your activity level, make sure your body is acclimated to the hotter weather. If you’re beginning to exercise outdoors for the first start with interval time frames and monitor your duration and intensity levels. Gradually increase your physical activity and monitor your progression.

    Drink fluids:
    I am not talking about alcohol on those hot summer days. Hydrate with water and do not wait until you are thirsty. Be proactive about your water consumption. With intense or prolonged exercise; consider sports drinks that are made for replenishing and restoring electrolyte balance.

    ACSM (American College of Sports Medicine) guidelines for hydration during exercise.

    • Drink 3-8 fluid ounces of water every 15- 20 minutes when exercising for less than 60 minutes.
    • Drink 3-8 fluid ounces of a sports beverage (5-8 percent carbohydrate with electrolytes) every 15-20 minutes when exercising greater than 60 minutes.
    Dress smart:
    Wear sunscreen to reduce risk of sunburn! Sunburns will reduce your body’s ability to cool itself. Light weight clothing that is also loose fitting will help keep you cooler. Synthetic fabrics such Dri-Fit wick moisture away from your skin and can promote evaporation of sweat and therefore keep you cooler.Medical conditions:
    Always talk to your doctor if you have known medical conditions to ensure safe methods of exercise in the heat.  Children and adults over the age of 65 are at greater risk for illness and symptoms related to over-heating.

    References:
    1. ACSM College of Sports Medicine. Selecting and Effectively Using Hydration for Fitness. https://www.acsm.org/docs/brochures/selecting-and-effectively-using-hydration-for-fitness.pdf. Accessed July 19th, 2015.2. Mayo Clinic. Mayo Foundation for Medical Education and Research. Heat and Exercise: Keeping Cool in Hot Weather. http://www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/exercise/art-20048167. Accessed July 10th, 2015.

    3. O’Conner FG, et al. Exertional heat illness in adolescents and adults: Management and prevention. Http://www.uptodate.com/home. Accessed July 19th, 2015.

    4. Tips for preventing heat-related illness. Centers for Disease Control and Prevention. http://www.bt.cdc.gov/disasters/extremeheat/heattips.asp. Accessed July 10th, 2015.