Gradual return to load after injury: principles of loading

After an injury the challenge is to find a load that rebuilds capacity without creating a new peak when returning to full training [2]. According to a Danish professional review of tendon treatment, what matters is the total load and how long the tendon is loaded. Different types of muscle work can be used [1].

The sources in this article mainly concern overuse in tendons, and running and sport. After fractures, surgery or larger injuries the plan may look different and must be clarified with your therapist.

In the review of tendon treatment, targeted exercise comes out better than waiting and most treatments without exercise. Long periods of inactivity can weaken the tendon [1]. At the same time, overload without enough recovery can damage it. The tendon's structure is fully restored only about 36 hours after a training session, and daily heavy training can therefore give too little rest [1].

Other activity that does not worsen the symptoms can maintain fitness and strength. Activity that causes pain should be limited [1].

The Danish review allows mild to moderate pain during exercise, up to 5 on a scale from 0 to 10. The pain should be back to the usual level the next morning, and it should not increase from week to week [1]. Markedly increased pain or a flare-up after a session suggests that the load was too high [1].

NHI.no describes the same principle in exercise advice for shoulder problems. Some discomfort must be expected, and if the pain is strong, the load is reduced. If it decreases from session to session, the load can be increased [4].

A systematic review of 30 studies of lower limb tendons found that pain was the most common criterion for increasing the load. There is little strong evidence that pain-based criteria are best, and the authors call for studies comparing different criteria in the same programme [3].

NHI.no points out that a sudden increase in training volume is regarded as a significant cause of soft tissue injuries. In a study of Australian football players, an increase of less than 10 percent per week was associated with a low risk of injury, while an increase of around 15 percent was associated with a markedly higher risk [2]. For runners, NHI.no recommends that weekly distance is not increased by more than 10 percent, and that hard sessions are followed by easier days [5].

The figures come from athletes and do not necessarily apply to everyone. After an injury the right pace will depend on what is injured and how the body responds.

After overuse in tendons, rehabilitation most often lasts 6 to 12 weeks, and some need a longer course. The earliest return to sport is after 6 to 8 weeks, and only when the strength of the tendon and the other muscles has been regained [1]. NHI.no gives 6 to 12 weeks for those who respond to an exercise programme for problems in the supraspinatus tendon of the shoulder [4].

The time frames apply to specific conditions. They show that rehabilitation often takes weeks to months, and that there are large individual differences.

A physiotherapist can examine what is injured, assess what you tolerate right now and make a plan for how the load can be increased over time. You can read more about physiotherapy with us. For tendon-related problems, shockwave therapy can be a supplement, and when the diagnosis is uncertain, diagnostic ultrasound can be used.

Should I rest completely when I have a tendon injury?

Long periods of inactivity can weaken the tendon. Targeted exercise comes out better than waiting, and activity that does not worsen the symptoms can continue [1].

How much pain is acceptable during rehabilitation?

The Danish review allows pain up to 5 on a scale from 0 to 10 during exercise, provided it is back to the usual level the next morning [1].

How much can I increase training from week to week?

In a study of football players, an increase of less than 10 percent per week was associated with a low risk of injury [2]. After an injury the pace depends on what is injured.

How long before I can train as before?

Rehabilitation after overuse in tendons most often takes 6 to 12 weeks or more, and the earliest return to sport is after 6 to 8 weeks [1].

When should I contact a doctor?

NHI.no recommends that you do not run through pain, and that you contact a doctor if pain from running lasts for more than a week [5].

The article on Achilles tendon pain describes loading exercise for a specific tendon. The page on supraspinatus tendinitis describes a corresponding condition in the shoulder. You can find more articles in the overview of articles.

This article was written by Dr.Dropin Fysikalske and is based on the sources listed below. It gives general information and does not replace an examination by a healthcare professional.

The websites were accessed and read on 22 October 2026.

1. Couppé C, Magnusson SP. Fysioterapi til idrætsudøvere med overbelastede sener (Physiotherapy for athletes with overloaded tendons). Faglig status. Danske Fysioterapeuter. 2019. Link

2. Kvam M. Kan økt treningsmengde beskytte mot skader? (Can increased training volume protect against injuries?) NHI.no. Last updated 8 March 2016. Link

3. Escriche-Escuder A, Casaña J, Cuesta-Vargas AI. Load progression criteria in exercise programmes in lower limb tendinopathy: a systematic review. BMJ Open. 2020;10(11):e041433. doi:10.1136/bmjopen-2020-041433. Link

4. Supraspinatustendinopati og treningsråd (Supraspinatus tendinopathy and exercise advice). NHI.no. Last updated 15 October 2024. Link

5. Løping - forebygging av overbelastning (Running - preventing overuse). NHI.no. Last updated 28 April 2023. Link