Swimming: What It Is and How to Read Your Own Swim Sessions

What swimming actually is, how your body moves in water, and how to log technique, safety, and training structure in your own notes.

Swimming is the self-propulsion of a person through water usually for recreation, sport, exercise, or survival. In this article, you will see how that simple idea turns into specific things you can notice and record in your own swim sessions.

What swimming actually is

Swimmers achieve locomotion by coordinating limb and body movements to achieve a level of buoyancy and hydrodynamic thrust that results in directional motion. When you write about a swim in your notes, you can describe which movements you focused on and how in control your body felt in the water.

Swimming is a whole-body exercise that requires endurance, skill, and efficient techniques to maximize speed and minimize energy consumption. You can treat every session as a chance to notice whether you were working more on endurance, on skill, or on efficiency, and label it that way in your log.

Swimming is consistently among the top public recreational activities, and in some countries swimming lessons are a compulsory part of the educational curriculum. Knowing whether you swam mainly for recreation, for structured training, or for a class can be a simple but useful line in your records.

As a formalized sport, swimming is featured in local, national, and international competitions including every modern Summer Olympics. Even if you are not competing, you can still borrow the idea of clear events and goals by naming the main purpose of each session in your notes.

A very short historical lens on your modern swim

Earliest records of swimming appear in Stone Age paintings dated around 7,000 years ago. You are adding your own tiny entry to that long history every time you log a session.

Written references to swimming date from around 2000 BC. You can think of your notes as one more written reference that future you can return to.

Herodotus described a failed seaborne expedition of Mardonius and noted those who could not swim perished or died from the cold. For your own records, it can be enough simply to note the water conditions and how confident you felt in them.

Buoyancy: why you float differently from day to day

The human body has an average relative density of 0.98 compared to water, which causes the body to float. When you are in the pool, you can pay attention to how easily you float at the start of a session versus the end.

Buoyancy varies based on body composition, lung inflation, muscle and fat content, center of gravity, and the salinity of the water. In your notes, you can describe your body position and how full or empty your lungs felt during float drills.

Higher body fat and saltier water both lower relative density and increase buoyancy. If you swim in different pools or open-water spots, you can jot down which ones feel easier to float in and how that changes your perception of effort.

Human males tend to find it more difficult to float because they usually have a lower center of gravity and higher muscle content. Whatever your own body type, you can use your log to record whether back floats and easy drills feel stable or challenging for you.

Because the body is supported by water, swimming is low-impact compared to land activities such as running. On days when you want a lower-impact session, you can tag your workout as a "swim day" and briefly explain why you chose it.

Strokes: what exactly you were doing in the water

Swimming involves repeated motions known as strokes to propel the body forward. Instead of only recording distance or time, it can help to write down which stroke pattern you used for each main set.

The four main competitive strokes are the front crawl (freestyle), breaststroke, backstroke, and butterfly. One simple structure for your training notes is to create a small section for each of these strokes and note how much time you spent on them in a given week.

The front crawl, also known as freestyle, is widely regarded as the fastest of the four main strokes. If a session focuses on speed, you can mark that it was mainly front crawl and write how it felt at different intensities.

Other strokes used in non-competitive swimming include the sidestroke and the survival backstroke. You can label any survival- or comfort-focused drills with these names so you remember which skills you practiced.

Human babies demonstrate an innate swimming or diving reflex from newborn until approximately ten months. If you are noting family or caregiving activities alongside your own training, you can simply record the age and type of water exposure without assigning it a performance goal.

Hydrodynamics and drag: technique details worth tracking

Water density and viscosity create resistance that both enables propulsion through strokes and generates drag on the body. A useful question for your log is which kind of resistance you were most aware of in a session: helpful grip on the water or tiring drag.

Hydrodynamics is important to stroke technique, and swimmers seeking greater speed or less exhaustion try to reduce drag either by increasing stroke power or reducing water resistance. In practice, you can write down whether you focused more on stronger pulls or on smoother, more streamlined body shapes.

Power must increase by a factor of three to achieve the same effect as reducing resistance. That number can remind you to give plenty of training attention to reducing drag, and you can note specific technique cues you used to do that.

Reducing water resistance involves adopting a horizontal water position, rolling the body to reduce breadth, and extending the arms as far as possible to reduce wave resistance. A simple checklist in your training notes can include "horizontal body", "body roll", and "long arms" so you can tick which elements you focused on in a given set.

Warm-up, strength training, and how you structure a week

Swimmers may perform pre-swim exercises such as arm swings to loosen joints and warm muscles immediately before swimming. When logging a session, you can briefly note whether you did these warm-up movements and how ready your shoulders and hips felt when you entered the water.

A 2022 systematic review found that adding certain strength training exercises to traditional swimming training may improve short and medium distance swimming performance and recommended separating strength sessions from swimming sessions while cautioning against increasing training volume too much. You can apply this by clearly marking in your planner which days or times are for dryland strength and which are for pool work, and by writing a quick note when you have changed your total weekly volume.

When you review your notes at the end of a week, you can check whether strength and swim sessions were separated the way you intended and whether any jump in overall training volume felt manageable.

Safety, environment, and equipment notes

Swimming carries risks such as incapacitation from panic and exhaustion that can lead to drowning, exposure to infection, and hazards from hostile aquatic fauna. In your log, you can add a short "conditions" line where you record whether you felt calm, tired, or uncertain in the water.

To minimize aquatic dangers, most facilities employ a lifeguard to watch for signs of distress. You can optionally note whether a lifeguard or other supervision was present during your swim, especially when you compare different locations.

Swimmers often wear specialized swimwear, but some swimmers may swim nude or in day attire depending on local culture. For your own record, you might simply note what you wore when you felt most comfortable and unrestricted in the water.

A variety of equipment can be used to enhance swimming experience or performance, including goggles, flotation devices, swim fins, paddles, and snorkels. Next to each workout, you can list which items you used and what they helped you focus on, such as vision, breathing, or leg drive.

Putting it together: how to review a week of swimming

At the end of a week, you can read back through your swim entries and highlight three themes: what strokes you used, how your body floated and moved, and how you structured warm-ups and any strength work.

On a fresh page, you can then write a short summary with headings like "Strokes", "Buoyancy and technique", "Safety and conditions", and "Strength and warm-up" and pull one or two key observations under each.

This kind of brief weekly review can help you decide simple adjustments for the next week, such as adding more time to a stroke you practiced less, or scheduling a separate slot for strength instead of attaching it to a long swim day.

Simple practice tasks to try

List the four main competitive strokes and add one note next to each about when you usually use it in your own sessions. Try this once and keep the list at the front of your training notebook.
Before your next swim, do a brief warm-up that includes gentle arm swings to loosen joints and warm muscles, then record in your log how your shoulders and upper body felt in the first few minutes of swimming. Repeat on another day without the warm-up and compare your notes.
During an easy session, experiment with floating while varying your lung inflation and body position, and write down how these changes affect your sense of buoyancy.
Pick one short set where you deliberately focus on a horizontal position, gentle body roll, and long arm extension, then note in your log whether the water felt smoother or more efficient compared with your usual stroke.
Look at your last week of training and sketch a simple plan that separates dryland strength sessions from swimming sessions, and write down how you will avoid increasing your total training volume too sharply compared with last week.
On your next visit to a pool or open-water site, quietly observe any visible safety measures such as supervision or posted guidance, and make a brief note about them alongside your session entry.

Use these tasks as gentle experiments in observation and note-taking, and adjust them to match your own comfort level and swimming experience.

This article is general health information and is not a substitute for medical diagnosis or treatment. Consult a healthcare professional if you have concerns.