Exercise and outdoor activities are important for strengthening the heart but “fun in the summer sun” must be done safely. Remember to always speak to your provider before starting any exercise program on your own.
AVOID HEAT & HUMIDITY
Patients with heart failure should not exercise outside when the temperature is too warm and humid. Reserve outdoor exercise time during the early morning or evening hours when the weather is cooler. If just sitting out in the sun too long, or in a house or car that does not have air conditioning, can place a patient at risk for heat exhaustion or heat stroke on an extremely hot, summer day. Move your exercise routine to a cool, air-conditioned building if possible. Patients with heart failure have less reserve to transport heat from the body and the heart can become overworked.
DECREASING RISK FOR DEHYDRATION & BALANCING FLUID SAFELY
It is particularly important to prevent dehydration because being dehydrated means your heart works harder to pump blood. This can cause your heart to beat faster, cause an irregular heartbeat or even palpitations. In addition, dehydration makes your blood thicker and constricts blood vessel walls. This can cause high blood pressure and put strain on your heart. Also becoming dehydrated can lead to lower blood pressure, which may cause dizziness. We all need to drink more replenishing fluids in hot weather and those with heart failure are no exception.
Balancing fluid in the body is a challenge for heart failure patients. Patients taking diuretics rid additional fluids in the body which makes it difficult to sweat. Heat and the humidity of the warmer weather reduces the amount of water in the body. Patients taking diuretic medications may need them adjusted during the summer months. Certain medications, such as beta blockers, ace receptor inhibitors, calcium channel blockers and diuretics can exaggerate how your body responds to heat, for example, when you have no fluid retention or when your blood pressure gets too low. ALWAYS talk to your provider with any medication questions or concerns before making any changes.
It is very importance to weight yourself daily, tracking and keeping a log of your morning “dry” weights (after first urination in the morning, before eating or drinking, and keeping the amount of clothing consistent when measuring weights from day-to-day). Call your provider if your weight goes up or down 2-3 pounds within 24 hours or 4-5 pounds within 7 days.
DON’T FORGET ABOUT SODIUM RESTRICTION
Keep total sodium intake 1.5-2.0 grams/24 hours (1500-2000 mg) helps to prevent the retention of fluid in the body. Try to avoid canned, processed, and prepacked foods, with known high sodium content. Read nutritional labels, including beverages, for sodium amounts per serving. Always be cautious when eating away from home.
GOOD REPLENISHEMENT
Staying hydrated for a heart failure patient is not always easy, especially with a fluid restriction directed by your provider. A fluid restriction is used to help avoid overloading your heart as more fluid in your bloodstream which makes it harder for your heart to pump. A restriction may be from 1.5 to 2L (48-64 oz.) per 24 hours. If you are on a fluid restriction, keep in mind fluids such as sugary sodas and full-strength juices slow down the passage of water from the digestive system to the bloodstream. Certainly, do not rely on caffeinated beverages or alcohol for fluid because they can cause or intensify dehydration. Most of your hydration should come from water (do not drink sports drinks like Gatorade and PowerAde, unless instructed by your health care provider, because of the added sodium and sugar). If you are on a fluid restriction, record your fluid intake to check you are within your daily limit. This may need adjusting in warmer weather, discuss with your provider. You should also include in your record foods that contain a lot of water, like gravy, fruit (especially watermelon), yogurt, jelly, etc.
Other examples of fluids:
- Sparkling water (no sodium or sugar added)
- Milk
- Soups and broths
- Ice cream and sherbet
- Popsicles
- Frozen yogurt
- Gelatin desserts (Jell-O)
- Tea and coffee (limit caffeine)
- Soft drinks (limit quantity, limit caffeine and sugar)
THIRST VS DEHYDRATION
Thirst is a natural function of your body to help maintain fluid balance. The sensation of thirst is a phenomenon experienced in nearly half of heart failure patients. Part of the sensation of thirst has to do with the physiology of heart failure as blood traveling to the kidneys is reduced, hormone interactions occur, stimulating thirst. For this reason, it is especially important to maintain fluid and electrolyte, such as sodium, balanced with heart failure, as to not worsen or activate further these physiological mechanisms. The feeling of thirst then does not always mean take in more fluids. So, thirst can be caused by fluid restriction, which is part of self-care management for some heart failure patients.
If you feel thirsty, try chewing gum, a sugar-free mint, or pieces of frozen fruit (such as grapes or strawberries). You can also rinse your mouth with water but do not swallow it, sip water and do not gulp it, or add natural flavoring with some berries or fresh squeezed lemon juice to water or a small cup of ice chips. If your lips feel dry, try lip balm.
Tips to Control Thirst on a Fluid Restriction:
- Use lip balm to keep your lips moist.
- Chew gum
- Suck on sugar-free hard candy
- Suck on lemon or lime wedges
- Have a breath mint (sugar free)
- Eat chilled or frozen fruits like grapes or strawberries
- Rinse your mouth or use oral swabs
Dehydration is different than being thirsty. You may be dehydrated if you have the following symptoms:
- Fatigue
- Weakness in your muscles
- Dark urine
- Headache
- Dizziness
- Dry mouth or skin
- Rapid heart rate
- Low blood pressure
- Sudden weight drop
- Urinating less frequently or in low volume
- Lethargy
- Fever
If you think you are dehydrated, call your provider right away!
Exercise contributes to a healthy lifestyle, but it is also just as important for heart failure patients to understand how constraints or precautions that should be taken seriously towards a safe and enjoyable summer! 
Fletcher, Gerald. (2015, July 31). Protect Your Heart in the Heat. Consumer Health Care. https://www.heart.org/en/health-topics/consumer-healthcare/what-is-card….
Marissa Burgermaster, PhD, MA,1 Rebecca Rudel, RD, MPH,2 and David Seres, MD, ScM, PNS, FASPEN (2020, July 17). Dietary Sodium Restriction for Heart Failure: A Systematic Review of Intervention Outcomes and Behavioral Determinants. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7704603
