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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 PQcSgYSNuwsJIyS4vxiWP2YjjfRhGHwRS6iE9+3jOm+Pis/qRlnP3o6BMcNN/Uts
 cmqslzms8VIcP0rj7Q49Ig==

<SEC-DOCUMENT>0001209191-08-026723.txt : 20080501
<SEC-HEADER>0001209191-08-026723.hdr.sgml : 20080501
<ACCEPTANCE-DATETIME>20080501120720
ACCESSION NUMBER:		0001209191-08-026723
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080429
FILED AS OF DATE:		20080501
DATE AS OF CHANGE:		20080501

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LIFE TIME FITNESS INC
		CENTRAL INDEX KEY:			0001076195
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-MEMBERSHIP SPORTS & RECREATION CLUBS [7997]
		IRS NUMBER:				411689746
		STATE OF INCORPORATION:			MN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2902 CORPORATE PLACE
		CITY:			CHANHASSEN
		STATE:			MN
		ZIP:			55317
		BUSINESS PHONE:		952-229-7543

	MAIL ADDRESS:	
		STREET 1:		2902 CORPORATE PLACE
		CITY:			CHANHASSEN
		STATE:			MN
		ZIP:			55317

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			VASSALLUZZO JOSEPH
		CENTRAL INDEX KEY:			0001180654

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-32230
		FILM NUMBER:		08793323

	BUSINESS ADDRESS:	
		STREET 1:		500 STAPLES DRIVE
		CITY:			FRAMINGTON
		STATE:			MA
		ZIP:			01702
		BUSINESS PHONE:		3019988100

	MAIL ADDRESS:	
		STREET 1:		1626 EAST JEFFERSON STREET
		CITY:			ROCKVILLE
		STATE:			MD
		ZIP:			20852
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-04-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001076195</issuerCik>
        <issuerName>LIFE TIME FITNESS INC</issuerName>
        <issuerTradingSymbol>LTM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001180654</rptOwnerCik>
            <rptOwnerName>VASSALLUZZO JOSEPH</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2902 CORPORATE PLACE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CHANHASSEN</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55317</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2163</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>60988</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Grant of restricted stock under Issuer's 2004 Long-Term Incentive Plan.</footnote>
        <footnote id="F2">Not applicable.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Amy C. Seidel on behalf of Joseph S. Vassalluzzo</signatureName>
        <signatureDate>2008-05-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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