Surgical Prehabilitation Protocol Guide

A surgeon named Rebecca Knackstedt tells a story about a patient who, on paper, was doing everything right. Knackstedt, a plastic and reconstructive microsurgeon at Duke University, met the young woman during chemotherapy: upbeat, hopeful, with a clear plan for breast reconstruction already in place. Then, in the months before her operation, the patient's life came apart. She developed metabolic syndrome, lost her hair, went through a divorce, lost her mother to breast cancer, lost her job, and became homeless (05:51). Knackstedt operated anyway, confident that good technique and a nudge toward more protein would be enough to heal her. It wasn't (06:10).

That failure reorganized her career. Knackstedt is a rare figure in academic medicine: an MD-PhD surgeon who also trained in functional medicine, a field she defines plainly as the belief that diet, sleep, stress, and disease are all connected rather than separate problems to be treated one at a time (03:50). Out of her humbling case, she built a research focus on what she calls prehabilitation, or prehab: doing before surgery the same work patients are normally assigned only afterward, in physical therapy.

"Prehab is just backing up before surgery and doing a lot of those same tools prior to the trauma that is surgery." — Rebecca Knackstedt [08:57]

The idea sounds soft until it gets specific. Knackstedt no longer tells patients to simply "get in the gym." She asks what movements they'll need after their particular operation and trains those muscles directly. A patient facing a flap reconstruction, which removes fat and skin from the abdomen and uses it to rebuild a breast, will lose core strength for weeks. So Knackstedt has her squat and strengthen her legs beforehand, since she'll need those muscles to get out of bed and off the toilet without her arms or her core (09:22). Patients who can already manage the small tasks of daily life, she has found, recover faster than patients who cannot, regardless of how much muscle mass a scan might show (11:31).

The Muscle Math

Surgery itself, Knackstedt explains, is a catabolic event, meaning the body breaks down protein rather than building it.

"Surgery in and of itself is a catabolic experience. As soon as you have surgery, you are going to experience protein breakdown." — Rebecca Knackstedt [65:18]

Some of that breakdown is useful: the body needs those amino acids to fight infection and heal wounds. But it draws down a limited reserve, and skeletal muscle is the reserve's biggest bank account. Muscle also absorbs glucose from the bloodstream, functioning as what Knackstedt calls a "sink" for blood sugar.

"Your muscle is your sink for your glucose, and if you're going to decrease your muscle mass, you're going to have high blood sugar." — Rebecca Knackstedt [66:03]

Less muscle means higher blood sugar, which is linked to worse healing, which then triggers more carbohydrate cravings and more blood sugar spikes. Knackstedt's answer is to raise the starting reserve before the surgical hit ever lands. She recommends surgical candidates aim for 2 grams of protein per kilogram of body weight daily, roughly one gram per pound (34:26). By contrast, national health survey data (NHANES) show the average American woman eats only 60 to 70 grams of protein a day, barely enough for one and a half meals (35:51). She has patients track their food for three days before changing anything, just to see the real gap (35:30).

Vitamin D gets the same upward revision. The standard lab range prevents bone problems like rickets, but Knackstedt argues it isn't high enough to support healing. She targets a level around 70 ng/mL for her surgical patients, both before and after their operation, a number she says aligns with what functional medicine physicians like Mark Hyman recommend (25:47). And she has helped push back against an older practice: routine bed rest. Surgical teams once assumed stillness let the body heal. The evidence now says the opposite. Early ambulation, meaning getting up and walking soon after surgery, lowers the risk of blood clots, shortens hospital stays, and slows the loss of lean muscle that bed rest accelerates (23:20).

The Five Days That Count

The most common pushback Knackstedt hears, including from fellow surgeons, is that none of this matters when a cancer patient has only a week before their operation. The literature disagrees. In studies of head and neck cancer patients, a notably sick population, just five days of immunonutrition, a mix of protein, healthy fats, and specific micronutrients, before surgery reduced complications, shortened hospital stays, and even lowered mortality (68:33). The five-day window was originally an arbitrary choice by researchers, but later studies kept confirming it (69:01).

Even one day counts. The night before surgery, once eating and drinking are about to be cut off, Knackstedt recommends a dose of 50 grams of simple carbohydrates, a practice called carbohydrate loading. It sounds counterintuitive for blood sugar, but she says it stabilizes glucose around the time of surgery, shortens hospital stays, and reduces post-operative pain, as long as the patient isn't diabetic or already struggling with blood sugar control (67:46).

Surgery also disrupts the gut microbiome, the community of bacteria living in the digestive tract, through antibiotics, anesthesia gases, pain medication, and diet changes (70:09). Knackstedt has patients take a probiotic before and after surgery, spaced four hours from any antibiotic dose so the antibiotic doesn't kill it. The specific strain matters less than the dose: large meta-analyses suggest at least 10 billion colony-forming units (CFU) is the threshold that actually does something (71:19).

Some of the newer tools sit at the more technical edge of her practice. Wound VACs, devices that apply gentle negative pressure over an incision, appear to speed healing and reduce fluid buildup; Knackstedt says she can often tell which patients had one within a week of surgery just by looking (54:17). Hyperbaric oxygen therapy, delivered in a hard chamber rather than the softer portable pods sold online, can soften radiation-damaged tissue (52:39), and a specialized installation wound VAC can help save infected breast implants over a course of one to five days (55:57). Both are backed by evidence for specific complications, not for general wellness (56:18).

None of this happens in a vacuum of pure biology. Knackstedt also spends time on subjects surgeons rarely raise: whether vaginal estrogen is safe for breast cancer patients (it is, and it prevents the urinary infections that can turn into life-threatening sepsis, at 12:40), why thermography, a heat-imaging technique promoted on social media, still isn't an adequate substitute for mammograms as a screening tool (28:48), and what she calls "anesthesia-associated depression," a low mood after surgery that she says is common, poorly understood, and worth naming in advance so patients aren't blindsided by it (45:23).

Why isn't any of this standard practice yet? Knackstedt names three obstacles. Insurance doesn't cover most of it, so recommending it can feel like asking financially strained cancer patients to spend more money. Surgical training doesn't teach it, so most surgeons simply don't know the evidence exists. And even willing surgeons struggle to fit it into overloaded clinics where physical therapists are booked six months out (74:29). Yet she argues the economics actually favor prevention: studies show that investing in prehabilitation saves money overall by avoiding complications, extra emergency visits, and longer hospital stays (76:13).

Knackstedt treats her patients' surgeries as routine.

"It is another day at work for me, but it is the biggest day in their lives, and it's an honor and privilege to be part of that." — Rebecca Knackstedt [77:06]

The gap in that sentence, between a Tuesday on her calendar and the most consequential day in someone else's life, is where prehabilitation lives. It doesn't promise a different outcome. It promises that whatever the outcome is, the body meets it from a stronger starting point.