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A long run is usually typical in a runner’s training schedule. Whether you’re training for a marathon, a half or even a 5K, going for a long slow distance (LSD) run can be advantageous to your training. Although we may be more than physically capable of running moderately fast on our distance days, our bodies often need a break with mild jogging. It’s important to give your legs that day to heal and recover from the hard, shorter work you’ve put in all week.
Not only is it a time for your body to mend, but LSD runs are a great way to build base that allows us to perform well on race day. Without base mileage, runners might train too hard too soon, often resulting in an injury. As is with many things, a base gives us that good foundation when choosing where to go next. Matt Forsman, a USATF/RRCA certified coach, explains that it’s essential to expose your body to gentle, consistent stress in order to develop the key systems to support the act of running. He also says you should gradually introduce running that’s a bit faster, if you desire. It’s the perfect way to prepare your body for higher-intensity training.
The book Running for Fitness explains that LSD runs give your joints and muscles endurance to tackle more mileage. It also helps to improve your cardiovascular system, which strengthens your heart, increases blood flow in your body, allowing more oxygen to be delivered to your muscles. Roger Sacks, a Beaumont exercise physiologist, explains that LSD running teaches your body to store more energy as glycogen in your muscles. In other words, fast-paced running relies on fueling the body with glycogen (carbohydrates) rather than fat. When you train at a slower pace, your body learns how to fuel with fat rather than glycogen. Sacks explains, “This type of training also uses a greater percentage of fat calories than higher intensity activity and helps with weight loss.”
LSD runs can also be a mentally rewarding aspect of your training. Regardless of how slow you go, being able to accomplish X amount of miles is satisfying. It also makes shorter runs feel like a breeze. For me, I find just being able to get out there and take in as much as I can for as long as I can is the most favorable part of LSD runs.
Keep in mind the old saying: “Slow and steady wins the race.” Some days, we are just meant to be the tortoise.