Unveiling the Mystery of Bone Stress Injuries: Understanding, Preventing, and Overcoming

Bone Stress Injuries (BSIs) often present with a history consistent with overuse injury—the gradual onset of activity-related pain. The bone slowly loses its ability to withstand repetitive running/jumping/landing. There is a continuum of decline starting from healthy bone, to stress reaction, with eventual porogression into stress fracture and potential full fractures.  

More Than Just a Fracture

Bone Stress Injuries (BSIs) arise due to an intricate interplay between the accumulation of microdamage within the bone structure and its subsequent repair. To understand this phenomenon, consider the analogy of strength exercises for muscles. Microscopic tears manifest in muscles during strength training, prompting subsequent repair, fortification and increased strength. 

A parallel process occurs in bones, albeit at a considerably more gradual pace. Engaging in activities like running, jumping, or skipping leads to microscopic damage in bone sections, initiating a reparative mechanism aimed at strengthening the affected areas. However, bone stress reactions develop when the pace of damage surpasses the capability of the repair process

  • A stress reaction is the early stage of bone overload, pain usually appears only during running and eases with rest. A stress fracture is a progression of this, often causing pain even when walking or at night. The only way to know for sure is through imaging, with MRI being the gold standard for diagnosis. Early identification makes recovery much quicker. If you’re displaying early warning signs the best next steps are to book in an assessment.

  • Sometimes, but it depends on the bone involved and how irritated it is. Lower-risk sites (like the fibula or second metatarsal) may allow for modified loading, while high-risk sites (like the femoral neck or navicular) usually require full rest. At the Running Room our physios can develop a graded plan so you maintain fitness without slowing healing.

  • Recurring stress injuries often mean the underlying cause hasn’t been fixed. Common reasons include training load spikes, weak hip or calf muscles, poor running mechanics, or low energy availability (RED-S). Rehab should always include strength, nutrition, and running technique work - not just rest.

  • Your bones need adequate fuel to repair and adapt. Runners who under-fuel or train in a calorie deficit can develop low bone density, menstrual irregularities (in women), and reduced recovery capacity. Ensuring good energy intake, calcium, and vitamin D supports bone repair and long-term resilience.

  • Your return should be gradual and based on pain-free walking and other clinical markers depending on the area of injury. From there, we often use a structured run–walk program, increasing time on feet before intensity or hills. Each progression should feel completely pain-free for at least a few days before moving on. Strength and cross-training continue alongside to rebuild load tolerance. Just because you may not be able to run, it doesn’t mean you can’t train other parts of your body which ultimately make your return to running much easier.

Risk Factors 

Modifiable:  

  • Rapid increase in running load - volume, intensity, frequency, terrain

  • Running more than 32 km per week

  • REDS (Relative enerrgy deficiency in sports)

  • Diet with insufficient calories, calcum or vitamin D

  • BMI < 19 

Non-Modifiable:

  • History of bone stress injuries - 5 fold increased risk

  • Caucasian race

  • Female > male 

  • If you played field based sports as a child before age 12

Clinical Presentation

Early Onset

  • Vague ache after activity

  • Warming up or reduction of symptoms with exercise

  • Lack of reproducibility during loading activities e.g. inconsistent pattern of discomfort

Mid to Late Onset 

  • Specific activities induce pain e.g. running, jumping or hopping

  • Diffuse ache at rest

  • Very sore to touch at specific location

  • High severity of pain during hopping tasks 

  • For females, loss of menstraul cycle

  • For males, loss of libido 

Safeguarding Your Bones: Prevention Strategies Unveiled

Monitoring Training Features:

Implementing periodisation, including rest days and planned breaks. A 10% reduction in load magnitude e.g. cutting out a speed session for a week can significantly extend the time before bone fatigue.

Environmental Factors:

Recognising the impact of terrain on BSI risk is paramount. Hilly and rocky terrains pose higher risks than flat surfaces. 

Road to Recovery: Managing Bone Stress Injuries

Initial Management:

Low Grade BSI - Level I-II

Activity modification takes center stage in the initial management Temporary discontinuation of running, coupled with modified activity, allows tissue-level healing. Pain-free walking and cautious use of assistive devices aid in minimizing load during recovery.

High Grade BSI - Level III-IV

Immobilisation or partial weight bearing for 6 weeks using a CAM boot or crutches 

Maintain Physical Conditioning:

Cardiovascular fitness and strength of non affected muscle groups must be maintained during recovery 

Mid to Long Term Management:

Resistance Exercises:

Weighted, high intensity, lows reps to the affected area 

Encourage Bone Development (Osteogenic Activity)

Powerful movements with low repetitions stimulate large amount of bone growth e.g. drop jumps.

Return to Run:

Once immobilisation devices have been weaned out, a return to run program will commence after one week of painless walking and the ability to complete 10 single leg hops without pain. Programs start with limited running and gradually increase over a 4-6 weeks period. 

Running Gait Retraining:

Faulty mechanics can impede healing or contribute to recurring injuries. Gait retraining techniques, including biofeedback, altered stride rate, and barefoot running, aim to reduce bone loading. 

Seeking Professional Guidance

For a comprehensive approach to overcoming bone stress injuries and enhancing performance, seek expert running physiotherapy. Specialised care is available in Sydney's Eastern Suburbs and London Battersea, providing tailored strategies for lasting relief and improved athletic performance.