Natick

This research aims to understand how eating shelf-stored tart cherry products affects the bodys ability to absorb and use compounds found in tart cherries. Researchers are studying this because tart cherry products may help reduce muscle damage and soreness and improve antioxidant capacity after exercise. The study involves active-duty military personnel and civilians aged 17 to 39 who are in good health and willing to follow study instructions. Participants will take part in a randomized, crossover study where they consume four different food products over four sessions with five-day breaks between them. These products include a commercial tart cherry juice, a snack bar with tart cherry powder, a powdered drink with tart cherry powder, and a control beverage without tart cherry. Each tart cherry product contains about 120 mg of anthocyanins, a key compound being studied. During each session, participants will fast overnight, have an IV catheter placed for blood sampling before and after consuming the product, and provide urine samples. Blood and urine will be tested for polyphenol levels and antioxidant markers at multiple time points up to 24 hours. The study will also explore links between the results and gut microbiome composition. Participation includes four sessions with detailed monitoring, and the study plans to collect complete data from up to 15 participants.

Researchers are studying how different types of energy bars affect the bodys use of fuel and aerobic performance during cold weather exposure. This randomized crossover study focuses on healthy adults aged 18 to 39 years who perform exercise in a cold environment 5C while wearing light clothing. The goal is to understand how bars higher in carbohydrate or higher in fat impact energy use and endurance during cold-weather military operations. Participants consume one of two types of isocaloric supplement bars approximately 350 kcal one higher in carbohydrates 50% carbs, 30% fat, 20% protein or one higher in fat 30% carbs, 50% fat, 20% protein. The order of consumption is randomized and double-blinded. After consuming the bar, volunteers rest for 60 minutes in cold conditions, then perform 90 minutes of treadmill exercise carrying a load equal to 30% of their body weight. This is followed by a 2-mile time trial to assess endurance performance. There is a minimum washout period of six days between trials. During the study, researchers collect baseline data height, weight, body composition, peak oxygen uptake and monitor core and skin temperatures continuously. Indirect calorimetry is used to measure substrate oxidation during exercise, and serial blood samples assess circulating substrates and hormones. Exercise and diet are controlled, including a lead-in diet 24 hours before each trial. The study measures endurance performance over 30 minutes and substrate oxidation over 90 minutes. Participants are asked to abstain from alcohol, nicotine, and other supplements during the study periods.

Researchers are studying how long-acting reversible contraceptives LARCs, such as implants and intrauterine devices, affect iron levels and how womens bodies respond to extreme environments like heat, cold, and high altitude. The study focuses on female military personnel and civilians aged 18 to 40 years. It aims to understand if using LARCs influences physiological reactions, such as sweating, skin blood flow, breathing, and heart rate, and to explore the prevalence of iron deficiency and anemia in women using these contraceptives compared to those using short-acting methods like oral contraceptives.

Researchers are evaluating the effects of intravenous iron compared to a placebo saline injection on oxygen levels in the blood, exercise performance, and treadmill running times during sudden exposure to low oxygen conditions simulating high altitude at about 4800 meters. The study aims to see if iron treatment improves oxygen saturation at rest and during exercise and if these improvements last for two weeks. The trial randomly assigns 24 healthy adults aged 18 to 40 to receive either Injectafer intravenous iron at 15 mgkg up to 1000 mg or a saline placebo. Participants undergo seven visits including initial assessments like body fat measurement using DEXA scans, lung function tests, and peak aerobic capacity. Exercise tests and blood samples occur before and after treatment during exposure to high altitude conditions. Participants will be carefully monitored through exercise performance tests such as a 2-mile treadmill time trial and measurements of oxygen saturation, ventilation, blood markers, and skin blood flow at sea level and simulated altitude. These assessments occur before treatment, and one and two weeks after treatment to track the lasting effects. The study includes safety checks and lasts through multiple visits over several weeks.

Researchers are comparing the rates of surgical and minimally invasive interventions, as well as any harms, in Medicare beneficiaries treated with the MILD procedure versus those treated with interspinous process decompression IPD for lumbar spinal stenosis with neurogenic claudication. This observational study uses Medicare claims data to follow patients for 24 months after their initial procedure starting from January 1, 2017. The purpose is to evaluate outcomes between these two types of procedures without requiring prior patient enrollment or consent. The study includes two groups patients who received MILD, which is a percutaneous image-guided lumbar decompression performed under fluoroscopic guidance through a dorsal approach to the spine, and patients who received IPD, a different device-based decompression procedure. Data on reoperations and complications will be collected for both groups over a 24-month follow-up period using Medicare claims. Enrollment continues until the sponsor decides to stop. Participants involvement is passive as the study uses existing Medicare claims data. Researchers will monitor rates of harms related to the initial procedure and subsequent surgical or minimally invasive interventions over two years. No direct patient visits or interventions are conducted, and the study is exempt from institutional review board oversight. The total study duration extends to December 2026, covering cases treated since early 2017.

Researchers are studying how different amounts of dietary protein affect muscle protein synthesis in healthy, active adults who experience muscle disuse due to injury. The study focuses on overcoming muscle loss caused by reduced muscle use, which leads to a negative balance between muscle protein breakdown and synthesis. This work aims to identify the optimal protein dose to stimulate muscle rebuilding during periods of immobilization to improve recovery from musculoskeletal injuries. Participants will undergo a randomized, double-blind study where one leg is immobilized using a knee brace fixed at about 60 degrees of flexion for five days, while the other leg remains active as a control. During immobilization, diets will be standardized. After this phase, participants will consume either 20 grams or 40 grams of whey protein as a beverage to evaluate muscle protein synthesis responses in both legs. Throughout the study, participants will undergo stable isotope infusions, blood draws, and muscle biopsies to measure muscle protein synthesis rates. Researchers will assess how muscle responds to the protein doses after immobilization, using advanced methods like 2H5-Phenylalanine stable isotope techniques. The trial will help develop nutritional strategies to preserve muscle mass and support recovery after injury. The study includes careful monitoring of diet, physical activity, and safety, with participation lasting at least the immobilization and protein feeding phases.

Researchers are evaluating the effect of spironolactone combined with standard care compared to standard care alone in patients with Heart Failure with Preserved Ejection Fraction HFPEF. This condition is common and serious, but currently lacks effective treatment. The trial is a phase 3 Registry-Randomized Clinical Trial RRCT involving patients from the Swedish Heart Failure Registry and the US. HFPEF is defined by heart failure symptoms, elevated NT-proBNP levels, and an ejection fraction of 40% or higher. Participants will be randomly assigned to receive either spironolactone added to their usual care or usual care alone. Spironolactone will be given as 25 mg tablets, starting at 25 mg per day with a possible increase to 50 mg daily if tolerated. If spironolactone is not tolerated, eplerenone may be prescribed instead. The control group will continue with their standard care without spironolactone. The study duration is planned for 9 years, with enrollment lasting 7 years. During the study, researchers will collect data on cardiovascular death and hospitalizations due to heart failure as the primary outcomes. Secondary outcomes include hospitalizations for various causes, adverse events, and treatment adherence. In Sweden, outcomes will be obtained by linking national registries, while in the US, sites and call centers will report outcomes. The trial aims to enroll approximately 2000 patients, with follow-up continuing for at least 5 years after study start to monitor these outcomes.