Vary Your Pace
"Doing a set, like 10 x 100, and holding the same pace for the whole set just makes you good at holding the same pace," Porter says. "When you're in a race, your heart rate is going to spike, so you might as well train for it." In a race, you typically go a little fast at the beginning, settle in, and then get faster at the end.
One of Porter's favorite ways to train the body to process these spikes in heart rate is with deck ups. Simply swim to the edge of the pool, push yourself up on to the deck, stand up, then jump back in and do the next set.
More: Step Up Your Swim Workouts With a Pace Clock
Check Your Head Position
"For about every inch of lift you have on your head, you're going to get almost a foot of sinking in your feet," Porter says. That pulls your hips down and creates drag, which slows you down.
One of the most effective ways to change your swim speed is to change your head position. Don't believe it? Test it yourself. Start with your eyes looking straight down at the pool and your arms straight out in front of you. See what happens when you lift your head inch by inch.
More: Kicking Drills for Better Body Position
Don't Just Pull the Water, Push It
Lots of people give up halfway through the stroke. "As soon as you reach your belly button, that's when you're going to push the water behind you," Valerio says.
If your stroke tends to fade out halfway through, Valerio recommends brushing your thumbs against your thighs.
More: Become More Efficient by Finishing Your Stroke
Test Yourself
"If you want to figure out if something works, swim 6 x 100 normally. Then make an adjustment and do another 6 x 100," Porter says. "Get the time and heart rate on each 100. If you swim faster and your heart rate stays the same, it works. If your time gets faster and your heart rate goes up, that's still OK. But if your time gets slower, and your heart rate goes up, that change doesn't work for you."
More: 2 Top Swim Workouts for Triathletes
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