UNITED STATES
                        SECURITIES EXCHANGE COMMISSION
                            Washington, D.C. 20549

------------------------------------------------------------------------------


                                 SCHEDULE 13G

                   Under the Securities Exchange Act of 1934
                               (Amendment No. )

                          HEALTH FITNESS CORPORATION
                          --------------------------
                               (Name of Issuer)


                    Common Stock, $0.01 par value per share
     ---------------------------------------------------------------------
                        (Title of Class of Securities)


                                   42217V102
                      -----------------------------------
                                (CUSIP Number)


                               December 31, 2006
                     -------------------------------------
            (Date of Event which Requires Filing of this Statement)


Check  the  appropriate  box to  designate  the rule  pursuant  to which  this
Schedule is filed:

                              [ X ] Rule 13d-1(b)

                               [ ] Rule 13d-1(c)

                               [ ] Rule 13d-1(d)

* The  remainder  of this  cover  page  shall be  filled  out for a  reporting
person's  initial  filing on this form with  respect to the  subject  class of
securities,  and for any subsequent  amendment  containing  information  which
would alter the disclosures provided in a prior cover page.

The  information  required  in the  remainder  of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities  Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the Act (however,  see
the Notes).


                         Continued on following pages
                              Page 1 of 11 Pages
                            Exhibit Index: Page 10





                                 SCHEDULE 13G

CUSIP No.: 42217V102                                        Page 2 of 11 Pages


------------------------------------------------------------------------------
1.    Names of Reporting Persons.
      I.R.S. Identification Nos. of above persons (entities only).

      MAGNETAR FINANCIAL LLC
------------------------------------------------------------------------------
2.    Check the Appropriate Box if a Member of a Group
      (a) [ ]
      (b) [ ]
------------------------------------------------------------------------------
3.    SEC Use Only
------------------------------------------------------------------------------

4.    Citizenship or Place of Organization

      Delaware
------------------------------------------------------------------------------
Number of           5.       Sole Voting Power                  1,571,400(1)
Shares              ----------------------------------------------------------
Beneficially        6.       Shared Voting Power                None
Owned by Each       ----------------------------------------------------------
Reporting           7.       Sole Dispositive Power             1,571,400(1)
Person With         ----------------------------------------------------------
                    8.       Shared Dispositive Power           None
------------------------------------------------------------------------------
9.    Aggregate Amount Beneficially Owned by Each Reporting Person

      1,571,400(1)
------------------------------------------------------------------------------
10.   Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
      Instructions)

      [ ]
------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

      9.99%(1) based on 19,001,771 shares outstanding as of November 10, 2006.
------------------------------------------------------------------------------
12.   Type of Reporting Person:

      IA; OO



------------
(1) In addition,  the Reporting Person may also be deemed to be the beneficial
owner of certain warrants to acquire 374,850 Shares.  The warrants,  which are
exercisable  immediately at the option of the holder, are subject to so-called
"blocker"  provisions  prohibiting  the holder from exercising the warrants to
the extent that such  exercise  would  result in the holder  being  deemed the
beneficial owner of more than 9.99% of the Shares then issued and outstanding.




                                 SCHEDULE 13G

CUSIP No.: 42217V102                                        Page 3 of 11 Pages


------------------------------------------------------------------------------
1.    Names of Reporting Persons.
      I.R.S. Identification Nos. of above persons (entities only).

      MAGNETAR CAPITAL PARTNERS LP
------------------------------------------------------------------------------
2.    Check the Appropriate Box if a Member of a Group
      (a) [ ]
      (b) [ ]
------------------------------------------------------------------------------
3.    SEC Use Only
------------------------------------------------------------------------------
4.    Citizenship or Place of Organization

      Delaware
------------------------------------------------------------------------------
Number of           5.       Sole Voting Power                  None
Shares              ----------------------------------------------------------
Beneficially        6.       Shared Voting Power                1,571,400(1)
Owned by Each       ----------------------------------------------------------
Reporting           7.       Sole Dispositive Power             None
Person With         ----------------------------------------------------------
                    8.       Shared Dispositive Power           1,571,400(1)
------------------------------------------------------------------------------
9.    Aggregate Amount Beneficially Owned by Each Reporting Person

      1,571,400(1)
------------------------------------------------------------------------------
10.   Check if the Aggregate  Amount in Row (9) Excludes  Certain  Shares (See
      Instructions)

      [  ]
------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

      9.99%(1) based on 19,001,771 shares outstanding as of November 10, 2006.
------------------------------------------------------------------------------
12.   Type of Reporting Person:

      HC; OO

------------
(1) In addition,  the Reporting Person may also be deemed to be the beneficial
owner  of  certain  warrants  to purchase 374,850 Shares. The warrants,  which
are  exercisable  immediately  at the  option of the  holder,  are  subject to
so-called  "blocker"  provisions  prohibiting  the holder from  exercising the
warrants to the extent that such  exercise  would  result in the holder  being
deemed the  beneficial  owner of more than 9.99% of the Shares then issued and
outstanding.




                                 SCHEDULE 13G

CUSIP No.: 42217V102                                        Page 4 of 11 Pages


------------------------------------------------------------------------------
1.    Names of Reporting Persons.
      I.R.S. Identification Nos. of above persons (entities only).

      SUPERNOVA MANAGEMENT LLC
------------------------------------------------------------------------------
2.    Check the Appropriate Box if a Member of a Group
      (a) [ ]
      (b) [ ]
------------------------------------------------------------------------------
3.    SEC Use Only
------------------------------------------------------------------------------
4.    Citizenship or Place of Organization

      Delaware
------------------------------------------------------------------------------
Number of           5.       Sole Voting Power                  None
Shares              ----------------------------------------------------------
Beneficially        6.       Shared Voting Power                1,571,400(1)
Owned by Each       ----------------------------------------------------------
Reporting           7.       Sole Dispositive Power             None
Person With         ----------------------------------------------------------
                    8.       Shared Dispositive Power           1,571,400(1)
------------------------------------------------------------------------------
9.    Aggregate Amount Beneficially Owned by Each Reporting Person

      1,571,400(1)
------------------------------------------------------------------------------
10.   Check if the Aggregate  Amount in Row (9) Excludes  Certain  Shares (See
      Instructions)

      [  ]
------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

      9.99%(1) based on 19,001,771 shares outstanding as of November 10, 2006.
------------------------------------------------------------------------------
12.   Type of Reporting Person:

      HC; OO


------------
(1) In addition,  the Reporting Person may also be deemed to be the beneficial
owner of  certain  warrants  to  purchase 374,850 Shares. The warrants,  which
are  exercisable  immediately  at the  option of the  holder,  are  subject to
so-called  "blocker"  provisions  prohibiting  the holder from  exercising the
warrants to the extent that such  exercise  would  result in the holder  being
deemed the  beneficial  owner of more than 9.99% of the Shares then issued and
outstanding.





                                 SCHEDULE 13G

CUSIP No.: 42217V102                                        Page 5 of 11 Pages


------------------------------------------------------------------------------
1.    Names of Reporting Persons.
      I.R.S. Identification Nos. of above persons (entities only).

      ALEC N. LITOWITZ
------------------------------------------------------------------------------
2.    Check the Appropriate Box if a Member of a Group
      (a) [ ]
      (b) [ ]
------------------------------------------------------------------------------
3.    SEC Use Only
------------------------------------------------------------------------------
4.    Citizenship or Place of Organization

      United States of America
------------------------------------------------------------------------------
Number of           5.       Sole Voting Power                  None
Shares              ----------------------------------------------------------
Beneficially        6.       Shared Voting Power                1,571,400(1)
Owned by Each       ----------------------------------------------------------
Reporting           7.       Sole Dispositive Power             None
Person With         ----------------------------------------------------------
                    8.       Shared Dispositive Power           1,571,400(1)
------------------------------------------------------------------------------
9.    Aggregate Amount Beneficially Owned by Each Reporting Person

      1,571,400(1)
------------------------------------------------------------------------------
10.   Check if the Aggregate  Amount in Row (9) Excludes  Certain  Shares (See
      Instructions)

      [  ]
------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

      9.99%(1) based on 19,001,771 shares outstanding as of November 10, 2006.
------------------------------------------------------------------------------
12.   Type of Reporting Person:

      HC


------------
(1) In addition,  the Reporting Person may also be deemed to be the beneficial
owner of  certain  warrants  to  purchase 374,850 Shares. The warrants,  which
are  exercisable  immediately  at the  option of the  holder,  are  subject to
so-called  "blocker"  provisions  prohibiting  the holder from  exercising the
warrants to the extent that such  exercise  would  result in the holder  being
deemed the  beneficial  owner of more than 9.99% of the Shares then issued and
outstanding.





                                                            Page 6 of 11 Pages


Item 1(a)   Name of Issuer:

            Health Fitness Corporation (the "Issuer")

Item 1(b)   Address of Issuer's Principal Executive Offices:

            3600 American Boulevard West, Bloomington, Minnesota 55431

Item 2(a)   Name of Person Filing:

            This Statement is filed on behalf of each of the following persons
(collectively, the "Reporting Persons"):

            i)    Magnetar Financial LLC ("Magnetar Financial");

            ii)   Magnetar Capital Partners LP ("Magnetar Capital Partners");

            iii)  Supernova Management LLC ("Supernova Management"); and

            iv)   Alec N. Litowitz ("Mr. Litowitz").

            This Statement  relates to Shares (as defined herein) and warrants
to acquire Shares (the  "Warrants")  held for the accounts of Magnetar Capital
Master Fund, Ltd, a Cayman Islands exempted company  ("Magnetar Capital Master
Fund"). Magnetar Capital Partners serves as the sole member and parent holding
company of Magnetar Financial.  Magnetar Financial is a registered  investment
adviser under Section 203 of the Investment  Advisers Act of 1940, as amended.
Magnetar  Financial  serves as investment  adviser to Magnetar  Capital Master
Fund. In such capacity,  Magnetar  Financial  exercises  voting and investment
power over the Shares held for the account of Magnetar  Capital  Master  Fund.
Supernova Management is the general partner of Magnetar Capital Partners.  The
manager of Supernova Management is Mr. Litowitz.

Item 2(b)   Address of Principal Business Office or, if None, Residence:

            The address of the principal  business  office of each of Magnetar
Financial,  Magnetar Capital Partners,  Supernova Management, and Mr. Litowitz
is 1603 Orrington Avenue, 13th Floor, Evanston, Illinois 60201.

Item 2(c)   Citizenship:

            i)    Magnetar Financial is a Delaware limited liability company;

            ii)   Magnetar Capital  Partners is a Delaware limited partnership;

            iii)  Supernova   Management  is  a  Delaware  limited   liability
                  company; and

            iv)   Mr. Litowitz is a citizen of the United States of America.






                                                            Page 7 of 11 Pages


Item 2(d).  Title of Class of Securities:

            Common Stock, $0.01 par value per share (the "Shares")

Item 2(e).  CUSIP Number:

            42217V102

Item 3.     If This  Statement  is Filed  Pursuant to  ss.ss.240.13d-1(b)  or
            240.13d-2(b) or (c), Check Whether the Person Filing is a:

            (a) [ ] Broker  or  dealer  registered  under  Section  15 of  the
                    Exchange Act.

            (b) [ ] Bank as defined in Section 3(a)(6) of the Exchange Act.

            (c) [ ] Insurance  company as defined in Section  3(a)(19)  of the
                    Exchange Act.

            (d) [ ] Investment  company  registered  under  Section  8 of  the
                    Investment Company Act.

            (e) [X] An   investment    adviser   in   accordance   with   Rule
                    13d-1(b)(1)(ii)(E);

            (f) [ ] An employee  benefit plan or endowment  fund in accordance
                    with Rule 13d-1(b)(1)(ii)(F).

            (g) [ ] A parent  holding  company or control person in accordance
                    with Rule 13d-1(b)(1)(ii)(G).

            (h) [ ] A savings  association  as defined in Section  3(b) of the
                    Federal Deposit Insurance Act.

            (i) [ ] A church plan that is excluded  from the  definition of an
                    investment   company   under   Section   3(c)(14)  of  the
                    Investment Company Act.

Item 4.     Ownership:

Item 4(a)   Amount Beneficially Owned:

            As of  February  5, 2007,  each of  Magnetar  Financial,  Magnetar
Capital  Partners,  Supernova  Management and Mr. Litowitz may be deemed to be
the beneficial  owner of the 1,571,400 Shares held for the account of Magnetar
Capital Master Fund.

            In  addition,  the  Reporting  Person  may  be  deemed  to be  the
beneficial owner of certain warrants to acquire 374,850 Shares.  The warrants,
which are exercisable  immediately at the option of the holder, are subject to
so-called  "blocker"  provisions  prohibiting  the holder from  exercising the
warrants to the extent that such  exercise  would  result in the holder  being
deemed the  beneficial  owner of more than 9.99% of the Shares then issued and
outstanding.

Item 4(b)   Percent of Class:

            The number of Shares of which each of Magnetar Financial, Magnetar
Capital  Partners,  Supernova  Management and Mr. Litowitz may be deemed to be
the beneficial owner  constitutes  approximately  9.99% of the total number of
Shares  outstanding  (based  upon  information  provided  by the Issuer in its
quarterly  report  on Form  10-Q  filed  on  November  14,  2006,  there  were
approximately 19,001,771 shares outstanding as of November 10, 2006).

Item 4(c)   Number of Shares of which such person has:

Magnetar Financial:
-------------------

(i) Sole power to vote or direct the vote:                         1,571,400(1)

(ii) Shared power to vote or direct the vote:                                 0

(iii) Sole power to dispose or direct the                          1,571,400(1)
disposition of:

(iv) Shared power to dispose or direct the                                    0
disposition of:

Magnetar Capital Partners, Supernova Management, and Mr. Litowitz:
------------------------------------------------------------------

(i) Sole power to vote or direct the vote:                                    0

(ii) Shared power to vote or direct the vote:                      1,571,400(1)

(iii) Sole power to dispose or direct the                                     0
disposition of:

(iv) Shared power to dispose or direct the                         1,571,400(1)
disposition of:

Item 5.     Ownership of Five Percent or Less of a Class:

            This Item 5 is not applicable.


-------------
(1) In addition, the Reporting Person may be deemed to be the beneficial owner
of certain  warrants to  purchase  374,850  Shares.  The  warrants,  which are
exercisable immediately at the option of the holder, are subject to so-called
"blocker"  provisions  prohibiting  the holder from exercising the warrants to
the extent that such  exercise  would  result in the holder  being  deemed the
beneficial owner of more than 9.99% of the Shares then issued and outstanding.




                                                            Page 8 of 11 Pages


Item 6.     Ownership of More than Five Percent on Behalf of Another Person:

            This Item 6 is not applicable.

Item 7.     Identification and Classification of the Subsidiary Which Acquired
            the Security Being Reported on By the Parent Holding Company:

            See disclosure in Item 2 hereof.

Item 8.     Identification and Classification of Members of the Group:

            This Item 8 is not applicable.

Item 9.     Notice of Dissolution of Group:

            This Item 9 is not applicable.

Item 10.    Certification:

            By signing below each of the Reporting  Persons certifies that, to
the best of their knowledge and belief, the securities  referred to above were
not  acquired  and are not  held for the  purpose  of or with  the  effect  of
changing or  influencing  the control of the issuer of the securities and were
not acquired and are not held in connection  with or as a  participant  in any
transaction having that purpose or effect.






                                                            Page 9 of 11 Pages


                                   SIGNATURE

            After  reasonable  inquiry  and to the  best of my  knowledge  and
belief,  I certify that the  information  set forth in this statement is true,
complete and correct.

Date: February 14, 2007              MAGNETAR FINANCIAL LLC

                                     By: Magnetar Capital Partners LP
                                         As Sole Member

                                     By:  /s/ Alec N. Litowitz
                                          ------------------------------
                                     Name: Alec N. Litowitz
                                     Title: Manager of Supernova Management
                                            LLC, as General Partner of
                                            Magnetar Capital Partners LP



Date: February 14, 2007              MAGNETAR CAPITAL PARTNERS LP


                                     By:  /s/ Alec N. Litowitz
                                          ------------------------------
                                     Name: Alec N. Litowitz
                                     Title: Manager of Supernova Management
                                            LLC, as General Partner of
                                            Magnetar Capital Partners LP

Date: February 14, 2007              SUPERNOVA MANAGEMENT LLC


                                     By:  /s/ Alec N. Litowitz
                                          ------------------------------
                                     Name: Alec N. Litowitz
                                     Title: Manager

Date: February 14, 2007              ALEC N. LITOWITZ


                                     /s/ Alec N. Litowitz
                                     ------------------------------



                                                           Page 10 of 11 Pages


                                 EXHIBIT INDEX


Ex.                                                                   Page No.
---                                                                   --------

A.    Joint Filing  Agreement,  dated February 14, 2007 by and among
      Magnetar  Financial LLC,  Magnetar  Capital Partners LP,
      Supernova Management LLC, and Alec N. Litowitz ...................... 11






                                                           Page 11 of 11 Pages


                                   EXHIBIT A

                            JOINT FILING AGREEMENT

            The  undersigned  hereby agree that the  statement on Schedule 13G
with respect to the Common  Stock of Health  Fitness  Corporation  dated as of
February 14, 2007 is, and any  amendments  thereto  (including  amendments  on
Schedule 13D) signed by each of the  undersigned  shall be, filed on behalf of
each of us pursuant to and in accordance  with the provisions of Rule 13d-1(k)
under the Securities Exchange Act of 1934, as amended.


Date: February 14, 2007              MAGNETAR FINANCIAL LLC

                                     By: Magnetar Capital Partners LP
                                         As Sole Member

                                     By:  /s/ Alec N. Litowitz
                                          ------------------------------
                                     Name: Alec N. Litowitz
                                     Title: Manager of Supernova Management
                                            LLC, as General Partner of
                                            Magnetar Capital Partners LP


Date: February 14, 2007              MAGNETAR CAPITAL PARTNERS LP


                                     By:  /s/ Alec N. Litowitz
                                          ------------------------------
                                     Name: Alec N. Litowitz
                                     Title: Manager of Supernova Management
                                            LLC, as General Partner of
                                            Magnetar Capital Partners LP


Date: February 14, 2007              SUPERNOVA MANAGEMENT LLC


                                     By:  /s/ Alec N. Litowitz
                                          ------------------------------
                                     Name: Alec N. Litowitz
                                     Title: Manager

Date: February 14, 2007              ALEC N. LITOWITZ


                                     /s/ Alec N. Litowitz
                                     ------------------------------