Swimming for sore knees, arthritis and life after physical therapy

If walking down a flight of stairs sends a twinge through your knee, a run is out of the question, and the gym leaves you sore for days, the pool starts to look different. It stops being a place for summer and becomes a place where you can still move.

AquaSkills, a private swim school at 88 Fulton Street in Lower Manhattan, offers fitness swimming for this reason. A quick note before anything else: nothing here is medical advice. Check with your doctor or physical therapist before you start any new exercise, and tell your instructor what hurts.

Three sentences the school puts front and center

On its fitness swim page, AquaSkills says: "Water takes impact out of exercise. Water reduces body weight by 90%. Water provides resistance in all directions." Those are the school's words, and they explain why many people with joint trouble look at water first.

Take them one at a time. If impact comes out of the movement, the knee is no longer absorbing a landing with every step. If the water carries most of your body weight, the joints carry less. And resistance in all directions means that moving an arm or a leg through the water works muscle on the way out and on the way back, without weights.

Who the school says fitness swimming is for

The school's fitness swim program is for all ages, and its page names arthritis, people who have finished physical therapy, and runners with knee trouble among the people it serves. It also lists rehabilitative swimming, weight-loss swimming, lap swimming with stroke definition, and water aerobics and aqua-pilates style exercises combined with swim skills. Lori Pailet, the school's director, is certified by the Aquatic Exercise Association, and the school says it has aquatic personal trainers.

Notice the phrase "combined with swim skills." You do not have to be a swimmer to start. If you cannot yet swim a length, the lesson can cover breathing, floating and moving through the water at the same time as the exercise.

That matters because many people who come to the pool for their joints have never been comfortable in it. Learning a little breath control and how to float first makes the exercise itself less stressful. You spend your attention on the movement, not on how safe you are, and that is a better use of a sore knee's good day.

Why a private lesson suits a sore body

Joint pain is specific. Your knee does not bother you the way someone else's does, and a group workout moves at the group's speed. A private lesson at AquaSkills means one student with one instructor and a flexible schedule, so the session can bend around what you can and cannot do that day.

The craft side is worth knowing about as well. Strokes load the body differently. Freestyle and backstroke use a flutter kick from the hips, while the kick in breaststroke asks something different of the knees, and some people find it uncomfortable. That is a reason to tell your instructor exactly where it hurts, and to ask your doctor, instead of guessing. A good instructor can choose a different stroke, shorten the range of motion, or use a kickboard to change how much work the legs do.

Water that is easy to get into

The AquaSkills pool is 15 feet wide and 60 feet long, heated to about 88°F all year. Stepping into warm water is easier than lowering stiff joints into a cold pool, and the small size means you are never far from the wall. Showers, locker rooms and blow dryers are available at the facility.

How to start without overdoing it

• Talk to your doctor or physical therapist first, and ask whether anything should be avoided.
• Tell the instructor about the knee, hip or shoulder before the lesson, not during it.
• Book the $98 intro class to see how the water feels before you buy anything bigger.
• Stop and say so if something hurts. Soreness from effort is different from pain.

The intro class is $98 per person and the school says you are not obligated to join afterward. Package prices are not published online, so ask when you text. To book, text (646) 724-7024.