Build Muscle

Inside the February Jacked-in-a-Box Sample Box

In February, M&F Editors picked these supplements for Jacked-in-a-Box members to try.

Inside the December Jacked-in-a-Box Sample Box


This fat burner provides multiple ingredients to help you reduce your fat stores while maintaining or building muscle mass. Coffea robusta, raspberry ketones and gingko biloba combine to release fat from storage and increase your metabolic rate. Amphetalean also contains choline bitartrate, phenylethylamine HCl and Evodia rutaecarpa extract, among others.

Get Amphetalean at the Muscle & Fitness Store >>



Promax LS (Lower Sugar) is an energy bar that was designed to support muscle growth while keeping fast, digestible carbs low to avoid insulin spikes. The chocolate fudge-flavored bar contains 18 grams of protein and 33 grams of carbs at 220 calories, including 14 grams of fiber, further reducing the impact of carbs.

Get the Chocolate Fudge Lower Sugar Bar at the Muscle & Fitness Store >>


Gaspari Nutrition

This pre-workout product contains two proprietary formulations, one to increase cellular energy and the other to excite the central nervous system. The
first formulation provides ornithine malate, carnitine tartrate and microencapsulated triacetin. The second contains N-acetyl L-tyrosine, caffeine, Citrus aurantium and other ingredients for enhanced focus. 

Get Superdrive at the Muscle & Fitness Store >>


High T
Sent to male members only

This product was developed to boost testosterone levels while keeping body fat in check. First, High T Black contains a metabolic enhancer with raspberry ketones and caffeine anhydrous. Its T-boosting blend includes fenugreek, Eurycoma longifolia and Tribulus terrestris, among others.

Get Black Hardcore Formulation >>



Members received samples of chocolate cake batter-flavored Syntha-6. Each serving delivers 22 grams of protein from a blend of six types of protein, including whey concentrate and isolate, micellar casein, calcium caseinate, egg and milk proteins. With 15 grams of carbs, Syntha-6 has only 200 calories per serving.

Get Syntha-6 at the Muscle & Fitness Store >>



Relying on fast-delivery technology, JetFuel Superburn helps you burn body fat through several different mechanisms. First, it helps maximize fat burning with
capsicum, Evodia rutaecarpa, Acacia rigidula and others. Second, a Camellia sinesis blend helps break down body fat. The delivery system fueled by MCTs ensures rapid absorption.

Get JetFuel Superburn at the Muscle & Fitness Store >>



This powdered form of ZMA adds ingredients to help support rapid recovery and enhance sleep. In addition to zinc, magnesium and vitamin B6, ZMA Nightcap contains 5-HTP, which boosts serotonin, helping to elevate mood and supporting deep sleep. Mix one serving with 4-6 ounces of water and drink 30-60 minutes before bed on an empty stomach.

Get ZMA Nightcap at the Muscle & Fitness Store >>


Jacked-in-a-Box members get the best deals on supplements, bar none. Sign up and you’ll receive:

  • At least 5 samples of new products (sometimes up to 10!)
  • A free workout from an M&F editor.
  • A full-year, print subscription to Muscle & Fitness, Muscle & Fitness Hers, FLEX, or Men's Fitness.
  • Free shipping on any order at The Muscle & Fitness Store and a promo code for $15 off your first $75+ order.
  • You’ll also get to write reviews to share with other readers—just like our editors.