Keeping a muscle clenched usually tires it out eventually, but that’s not the case for sphincters, which do things a little differently.

Physiatrist and engineer Todd Kuiken is building a prosthetic arm that connects with the human nervous system -- improving motion, control and even feeling. Onstage, patient Amanda Kitts helps demonstrate this next-gen robotic arm.

Hank tells us the story of the complicated chemical dance that allows our skeletal muscles to contract and relax.

Why do our muscles get tired and sore after exercise? Explore how our muscles function, and how you can exercise longer without experiencing muscle fatigue. -- You're lifting weights. The first time feels easy, but each lift takes more...

Today we are investigating our moral obligations to our parents and our families. Do we owe our parents anything as adults? Would it be a good idea to license parents? We’ll explore these questions as well as the ethics of care, and some...

Today we explore the penultimate ethical theory in this unit: contractarianism. Hank explains Hobbes’ state of nature, and implicit and explicit contracts, as well as the Prisoner’s Dilemma, and the benefits, and costs, of violating...

Neutron stars are some of the strangest things in the universe, but are they the source of the mysterious Fast Radio Bursts? Or is it aliens? Spoilers: probably not aliens.

Each time you take a step, 200 muscles work in unison to lift your foot, propel it forward, and set it down. It's just one of the many thousands of tasks performed by the muscular system: this network of over 650 muscles covers the body...

Muscle knots: more mysterious than you think!

We're kicking off our exploration of muscles with a look at the complex and important relationship between actin and myosin. Your smooth, cardiac, and skeletal muscles create movement by contracting and releasing in a process...

Paul Andersen explains the three types of muscle found in humans; striated, smooth and cardiac muscle. He explains how actin and myosin interact to contract the sarcomere in a muscle. The sliding filament theory explains how ATP and...

A SciShow Kids viewer wants to know: How Do Our Bodies Move? Jessi explains, while Squeaks works out!

The generally accepted negotiating style in Singapore businesses is a win-win approach that is achieved through compromise. Cutthroat tactics are not recommended. The goal is to arrive at an agreement that is beneficial to both parties....

It’s easy to understand that successful business negotiations in Mexico begin with strong business relationships. Learn more about how to develop trust and when to engage lawyers. Become familiar with the local expectation that written...

Japan’s legal system is based mainly on the model of prewar German and Soviet legal theory. Thus, the system is grounded not in judicial precedent but in the laws of the constitution. Culturally, the Japanese aren’t very litigious; they...

Maintaining harmony is an essential aspect of Japanese business culture, including negotiations. To the Japanese, negotiations are a fluid process based on diligent preparation and mutual respect. Learn more about how indirect...

Communication styles vary by region; Brazilians, for instance, tend to communicate indirectly. Learn how these cultural nuances impact negotiations. Review tips for negotiating effectively—essential for any business endeavor—and...

The video discusses the importance of communication with employers when juggling multiple jobs, particularly regarding coordinating schedules to prevent conflicts. It also touches on the potential implications of non-compete clauses and...

Howcast - Cell phone contracts might seem iron-clad, but loopholes may let you get out of your plan without paying a dime.

Howcast - Let belly dancer Irina Akulenko teach you how to do the belly dance move known as a vertical figure 8 in this Howcast video.

Howcast - Let belly dancer Irina Akulenko teach you how to do interior hip circles in this belly dancing video from Howcast.

Howcast - Let belly dancer Irina Akulenko teach you how to do a belly roll in this belly dancing video from Howcast.

Howcast - Let belly dancer Irina Akulenko teach you how to isolate your upper abs in this belly dancing video from Howcast.

Howcast - Let belly dancer Irina Akulenko teach you how to isolate lower abs in this belly dancing video from Howcast.