Factors That Affect Your Pulse & Heart Rate
When the body’s immune system becomes compromised—for example, with fever, injury, anemia, or infection—changes in heart rate can occur. Particularly if septic shock sets in, the heart rate will naturally quicken to meet oxygen demands.
I’m sure when the stress gets heavy; you’ve noticed that your body naturally responds with a quickening pulse. The same goes for fear, another type of anxiety, which prompts the flight response and releases hormones that make the heart pump faster.
During normal respiration the heart rate tends to slow faintly during inspiration (as you take breath in).
All types of over the counter, prescription, herbal supplements, and illegal drugs will have an impact on your heart rate. For instance, ephedrine or cocaine will increase it; while beta blockers and Valerian calm and slow it down.
If the glycogen stores in your body diminish, you will suffer fatigue. However, to properly fuel muscles, your heart rate will naturally increase to boost your energy levels.
When the body becomes dehydrated (following lack of fluids over an extended period) the blood thickens and waste clogs the bloodstream. Your heart will naturally work harder to flush out waste and maintain normal cardiac output.
Time of training
Heart rates tend to be lower in the morning.
The difference in heart rate between running in the morning and afternoon is typically about 5 to 6 beats per minute, but can be as great as 10 beats per minute. Your maximal heart rate is also several beats per minute lower in the morning. This means that if you set your heart rate zones based on your morning heart rates, and train in the afternoon, then you will train a bit less intensely than planned. Similarly, if you use afternoon or evening heart rates to determine your training zones, and then train in the morning, you will train somewhat harder than planned. That’s also the reason why we work with a bandwith of 10 beats to tackle this issue
Humidity Hinders Cooling
Relative humidity is the amount of water in the air compared to the theoretical maximum amount of water in the air and it directly influences sweating and cooling.
Remember that the body cools itself with the evaporation of sweat — not the sweating itself. The more humid it is, the more saturated the air becomes with water, and the harder it becomes to evaporate sweat. With less evaporation of sweat, we don’t cool as well. Plus, that sweat remains on the skin, making it seem like you’re sweating more, but you’re not — that’s the lack of evaporation.
An extremely important factor affecting exercise heart rate is temperature. Warmer temperatures cause the heart to beat faster and place considerable strain on the body. Simply put, when it is hot, the body must move more blood to the skin to cool it while also maintaining blood flow to the muscles. The only way to do both of these things is to increase overall blood flow, which means that the heart must beat faster. Depending on how fit you are and how hot it is, this might mean a heart rate that is 20 to 40 bpm higher than normal. Fluid intake is very important under these conditions. Sweating changes blood volume, which eventually can cause cardiac problems. The simplest and most effective intervention to address high temperature and heart rate is regular fluid intake. This helps to preserve the blood volume and prevent the heart from beating faster and faster.
Heart rate during running varies by a few beats from day-to-day. Several studies have found that heart rate during running at a given pace varies by a few beats per minute from day-to-day. It is not clear why this occurs, but most physiological variables exhibit similar amounts of day-to-day variation. This means that if you monitor your heart rate religiously, you will find that some days it appears you are getting slightly fitter and other days it appears you are getting out of shape, when in fact, your fitness level may not be changing. You should be cautious, therefore, in interpreting the results of any one session of heart rate monitoring. Do not put too much emphasis on small changes of 2 to 3 beats per minute in heart rate found during one run. When you find a systematic reduction in heart rate at a given pace, however, you can be confident that your fitness has improved. Similarly, if you find that your heart rate is consistently higher than expected, you can confidently conclude that something is wrong; i.e. you may be losing fitness or (more likely for most runners) overtrained.
Training heart rate does not predict racing heart rate.
During competition, your heart rate does not increase logically with your running speed. So many other factors affect your heart rate while racing, that it is not a good indication of how fast/hard you are running. If you measure your heart rate at your desired race pace during training, and use that heart rate to determine how fast to run during a race, then you will run quite a bit slower than planned, because with the excitement of the race, your heart rate will be elevated. You could account for the increase and still use your heart rate to accurately select your race pace if the increase in heart rate due to racing was consistent. Unfortunately, how much higher heart rates are at a given pace during racing compared to training has been found to vary greatly from person to person and from race to race.
Factor affecting resting heart rate is state of recovery. After exercise, particularly after a long run or bike ride, several things happen in the body. Fuel sources are depleted, temperature increases, and muscles are damaged. All of these factors must be addressed and corrected. The body has to work harder, and this increased work results in a higher heart rate. Even though you might feel okay at rest, your body is working harder to repair itself, and you’ll notice an elevated heart rate. Monitoring your resting heart rate and your exercise heart rate will allow you to make appropriate adjustments such as eating more or taking a day off when your rate is elevated.
One of the most valuable long-term pieces of information you can gather is resting heart rate. When you wake up each morning, take a minute to get an accurate resting heart rate and keep a log. You’ll find this an invaluable tool, providing feedback on injury, illness, overtraining, stress, incomplete recovery, and so on. It is also a very simple gauge of improvements in fitness. We know athletes who have gathered resting heart rate data for years and in a day or two can identify a 1 or 2 bpm elevation that precedes an illness or a bonk session. Some newer heart rate monitors have the capacity for 24-hour monitoring.