Cook the whole wheat rotini in boiling water according to package directions until al dente, then drain and rinse with cold water to stop the cooking process.
Season the chicken breast with a pinch of sea salt and black pepper, then grill or pan-sear over medium-high heat until the internal temperature reaches 165°F.
Let the chicken rest for 5 minutes before dicing it into bite-sized cubes.
In a small glass jar or bowl, whisk together the extra virgin olive oil, lemon juice, lemon zest, minced oregano, parsley, sea salt, and black pepper until the dressing is well emulsified.
In a large mixing bowl, combine the cooled pasta, diced chicken, halved cherry tomatoes, and diced cucumber.
Drizzle the lemon-herb vinaigrette over the salad and toss thoroughly to ensure every ingredient is coated.
Gently fold in the fresh baby arugula just before serving to keep the greens vibrant and crisp.