Antagonistic muscle groups

1. How muscle pairs work

An agonist helps produce the action being discussed. An antagonist can produce the opposing action at that joint. These are roles, not permanent labels: when you bend your elbow, the elbow flexors act as agonists; when you actively straighten it, the elbow extensors take that role. Supporting muscles also stabilize joints or assist the movement. An antagonist and a stabilizer are not necessarily the same thing. [1]

During real movement, opposing muscles may work together to control a joint. A muscle can generate force while shortening (concentric), lengthening (eccentric), or holding approximately the same length (isometric). Training should develop controlled movement, not simply the ability to move a heavier weight.

2. Major muscle groups and practical examples

The actions below identify useful opposing relationships. Exercise examples are learning options for your coach, not extra work to add to today's prescription.

Push and pull are broader movement categories. A row paired with a push-up is useful programming, but the many muscles involved do not form one simple antagonist pair. Likewise, the rotator cuff, shoulder-blade muscles and trunk coordinate several actions. Dead bugs and bird dogs emphasize trunk control; they are not a direct test of “abdominal versus back strength.”

3. Why swimmers train both directions

Swimming repeats some actions thousands of times. Dryland gives coaches a way to develop capacities that may receive less attention in the water, while maintaining the strength already present. For our JR / SR program, that means deliberate attention to knee flexion, hip control, shoulder external rotation, shoulder-blade coordination and trunk stability.

Research in young competitive swimmers supports this focus. A 16-week randomized study found improvements in external-rotator strength and shoulder-rotator balance with supplementary strength work. [3] Another 12-week adolescent study found greater external-rotation strength gains, but no significant difference in shoulder soreness between groups. [4]

4. What does a hamstring-to-quadriceps ratio of 40% mean?

If the hamstrings and quadriceps are measured under a compatible, standardized strength-testing protocol, a ratio of 0.40 means the hamstring result is 40% of the quadriceps result. For example, 40 N·m of knee-flexion torque divided by 100 N·m of knee-extension torque equals 0.40, or 40%.

A leg-curl weight divided by a leg-extension weight is not a clinical torque ratio. Machine leverage, setup, range, speed and effort differ. Do not use different machine stacks, repetition counts or exercises to label an athlete injured or “unsafe.” Record these as exercise-specific training measures instead.

Conventional testing compares concentric hamstring and quadriceps torque; functional testing commonly compares eccentric hamstring torque with concentric quadriceps torque. Values depend on the method, speed and joint position. A systematic review found limited value in using H:Q ratios alone to predict future hamstring or ACL injuries. [5]

Use a reported 40% finding as a reason to verify the measurement and review the whole athlete. A qualified assessor can interpret a standardized result. Our coaching goal is better capacity and control with appropriate recovery, not forcing every swimmer to reach an arbitrary percentage in three months.

5. Applying antagonistic training in our dryland sessions

The calendar provides the actual prescription. The examples below explain its purpose; they do not replace individual coaching.

Six calendar sessions do not mean six hard lifting days. Coaches must coordinate dryland with swim load, meets, soreness and recovery. NSCA youth guidance generally recommends resistance training on two or three nonconsecutive days each week; additional calendar slots can be technique, mobility or recovery sessions. Alternating “upper” and “lower” labels alone does not guarantee recovery. [2]

When a supporting movement needs attention, practice it early while fresh. Use a load that permits controlled repetitions and normal breathing. Keep the stronger pattern in the plan, but let the coach decide whether it needs less volume. Avoid adding extra sets just to make two numbers match. Rest enough to repeat the demonstrated technique; a paired exercise is not a race.

Progress one variable at a time—control, comfortable range, repetitions or resistance. A familiar movement performed well is more useful than constant novelty. Preserve the assessment exercises even when the training exercises vary.

6. First three months: test monthly, coach continuously

Use the scheduled monthly assessment session for each of the first three months. Establish a starting record before progressing load; this can be part of initial familiarization rather than a separate maximal test. Monthly reviews guide adjustments and do not guarantee a fixed rate of change.

1. Month 1 · Establish repeatable technique. Confirm equipment fit, comfortable range, pain-free execution and consistent instructions. Choose a few repeatable measures the athlete understands.
2. Month 2 · Compare like with like. Repeat the same protocol. Review attendance, swim load and recovery alongside the result. If technique or setup changed, document it instead of calling the difference a strength gain.
3. Month 3 · Review the trend. Look for improved control, tolerated workload and repeatable strength measures. Continue useful progressions; change the plan if fatigue, symptoms or inconsistent testing obscure the picture.

What to record privately

• Date, assessor, exercise or test, equipment, seat settings and body position.
• Side tested, range, movement speed, warm-up, repetitions or hold time, rest and units.
• Load or measured force/torque, technique observations, effort and any symptoms.
• Recent training, illness, fatigue and modifications that affect comparison.
• One practical next step, plus the conditions for progressing or reducing work.

Submaximal gym measures can track an athlete's progress within the same exercise. They are not interchangeable with clinical dynamometry. Stop a test for pain or loss of position. Persistent pain, unexplained weakness or a marked asymmetry warrants assessment by a qualified sports clinician; do not solve it by simply adding resistance.

7. Athlete checklist

• I know the action I am training and can demonstrate it before adding weight.
• I follow today's assigned load and tell my coach about pain or unusual fatigue.
• I control the return phase and use the agreed range of motion.
• I leave assessment results in my private training record, not a public ranking.
• I understand that progress means useful movement and capacity—not winning a ratio.

8. Supporting Articles & scientific references

Peer-reviewed research is linked below with its practical relevance and limits. Study findings are distinct from the coaching applications in this guide.

1. OpenStax. Anatomy and Physiology, §11.1. Textbook explanation of agonists, antagonists and synergists; an anatomy reference rather than a journal trial. Read anatomy chapter.
2. Faigenbaum AD et al. (2009). Youth resistance training: updated position statement paper from the National Strength and Conditioning Association. Journal of Strength and Conditioning Research, 23(Suppl 5), S60–S79. Supervision, age-appropriate progression and recovery guidance; not a swimmer-specific ratio prescription. Journal record · Free full-text PDF.
3. Batalha N et al. (2015). Does a land-based compensatory strength-training programme influences the rotator cuff balance of young competitive swimmers? European Journal of Sport Science, 15(8), 764–772. A 16-week randomized study in young male swimmers; supports external-rotator development, with limits on generalizing to all swimmers. Journal article · Abstract.
4. Manske RC, Lewis S, Wolff S, Smith B. (2015). Effects of a dry-land strengthening program in competitive adolescent swimmers. International Journal of Sports Physical Therapy, 10(6), 858–867. Small 12-week study: external-rotation strength improved; shoulder soreness did not differ significantly. Free full-text journal article.
5. Kellis E, Sahinis C, Baltzopoulos V. (2023). Is hamstrings-to-quadriceps torque ratio useful for predicting anterior cruciate ligament and hamstring injuries? A systematic and critical review. Journal of Sport and Health Science, 12(3), 343–358. Explains measurement differences and the limited predictive value of a ratio alone. Journal article · Free full text.

Educational guidance for supervised training. Individual testing, rehabilitation and return-to-sport decisions require an appropriate qualified professional.

← Dryland Library · Open training calendar →